He is stealing her blood. He's not even being subtle about it. (Does he think she's, like, a stupid child? Even someone who totally believed the "it's not for summoning demons, I just need to look at it" story would still have noticed him hiding it away after saying he wouldn't!)

She grabs the knife and lunges for the fridge. She probably can't win the fight, especially not with the broken leg, but she might be able to get back her blood and make him really regret trying to steal it for Evil rituals. (Blood first, though, if she can get back the blood it'll at least stop him from, like, binding her soul to use as fuel for a construct of Hell. Unless you can still do that sort of thing with dead people's blood, she's not sure—)

(He does in fact think she's a stupid child.)

His first instinct is to lean against the fridge to keep it closed - she's a small girl, she doesn't register as a real threat, and there's a lot of important supplies in there.  "What the hell are you doing, put that down!"

In that case she's going to try to stab him!!

(This would probably be more effective if she didn't have a broken leg.)

He was treating this as a panicking girl situation, not as a combat situation, so she does succeed in stabbing him.  (He's going to feel like such an idiot about it later.)  That's enough for his long-unused combat instincts to kick in, so he has her pinned on the ground and the knife tossed in a corner only a few seconds after he shouted for help.

A few people run in.  He yells that the mad girl stabbed him with a knife, which sure explains the otherwise pretty bizarre situation.  One of the other men takes over holding her down; someone takes care of the doctor's bleeding while discussing with him whether this is an ambulance situation or a normal ER one.  A minute or two later the director comes in and takes charge - Agnieszka gets searched, not particularly gently, and they take away any objects they find.  Then a man picks her up over his shoulder, carries her to an empty room in the basement, and locks her in there, without the crutches or her rucksack or anything else.  He does turn the light on.  Nobody particularly hits her in the process.

They look through her rucksack and anything else she had on her, listen to the doctor's baffled explanation of how much she objected to things being done with her blood, and try to figure out what the fuck to do next, but it'll definitely take them at least a few hours.

She keeps trying to attack the people who come in to help the doctor-ritualist. She's fighting like her life depends on it, because as far as she knows it does, but there's only so much she can do once they've got her hands and functioning leg pinned, at least if they're staying out of biting range.

(Her clothing has no unexpected objects. Her rucksack has a waterskin, a couple of rolls of bread that look suspiciously similar to the bread they serve in the orphanage, and a few identical pieces of paper with a woman's face stamped on and — random squiggles? foreign writing? whatever it is, it doesn't look familiar — on both sides.)

They're going to kill her. If she's very lucky they'll just torture her to death, and use her blood for a ritual that's Evil but not damaging to her, but she probably won't be lucky. When it was just the doctor there was a chance that it was just him, that he had somehow kept it secret, but if everyone else is also in on it she's going to die. 

Is there anything in the basement? Ritual equipment she can try to destroy, or anything like that? It won't save her, but anything that hurts the ritualists is better than nothing. (Presumably they didn't leave her with a means of suicide.)

If she's fighting that much then it takes two or three people to get her down to the basement, with a lot of swearing, and probably someone does hit her in the process, just to get her to stop for a moment, not that it works.

All the effort is not great for her leg, either - it definitely hurts now, in a different way than whatever surface bruises and scrapes she picked up in the process.

There's nothing at all in the basement room, except a rounded light attached directly to the ceiling (not dangling down from it like some of the other ones she's seen), with some thin metal bars around it.  She could probably jump up to it if she tried, it's not a very high room.  The lightswitch is outside the door and she can't get to it.

... Well, that's going to be a longer conversation involving several people, some of them also with scratches and bruises.

"What the fuck just happened?"

"I don't know!  Andrzej said she thought he was stealing her blood for satanic rituals or something, and it's not like I don't believe him, but... what??"

"Either she's just crazy - she probably is, she bit me, the little bitch - or... she really did grow up in some kind of horrifying cult out in the woods?"

"If she did then why won't she just tell us??"

"If you grew up in some kind of horrible place and just got out and had no idea what the rest of the world was like, would you tell random strangers the truth?"

"Yes!!"

"Okay, maybe you would, but I sure wouldn't.  I'd be scared that everyone else is horrible too.  She's acting about like that.  She fought like she thought we were going to murder her or something!"

"I still think she's probably just crazy, but... yeah, you have a point."

"You both have a point, but that doesn't tell us what we're going to do with her!"

"Juvie, of course, she stabbed a man with a knife!  He's in the hospital, for fuck's sake!"

"Yes, I know that's really what's supposed to happen, but... can you imagine that going well?  I sure can't.  She's just going to stab someone there too, probably sooner rather than later given how the place is, and then what?"

"And then they'll put her in isolation and she'll be even less our problem!"

"Yeah, they will, and she'll go crazy if she isn't already, and - if she really is some abused kid from a fucked-up cult, I'm going to feel guilty about it when I retire, you know?  She doesn't need discipline like all those criminal kids in there, she needs - I don't even fucking know, she needs to make sense."

"Well, we sure can't keep her, can you imagine if this happens again?  With one of the smaller kids instead of a grown man?"

"I don't think she'd go for someone who didn't seem threatening to her..."

"Are you sure enough of that?"

"No, I'm not."

A sigh.  "Well, either way I think we need to report this to the police and let them talk to her about this fucked-up cult in the woods or whatever she's talking about."

"Much good it's going to do them. But yeah, you're right, if something like that is going on then someone needs to know."

Someone calls the police.  They'll be here in half an hour or so, and in the meantime everyone needs to try to get the rest of the kids calmed down and back on schedule, and also figure out how exactly they're going to question the girl without her trying to scratch everyone's eyes out again.

She is not going to try to jump for the caged Light. Even if she can manage it with a broken leg, she definitely can't do anything about the bars. She spends a couple of minutes trying to ineffectually dig her way out but gives up when it gets obvious that the basement is made of a weird kind of rock rather than a weird kind of dirt.

Yes, it's weird rock in all directions.  She can maybe scrape some plaster off the wall before getting to more weird rock.

In that case the next thing that happens, maybe an hour later, is a voice at the door.  "This is the police. We just want to talk to you, but if you try to attack us when we open the door it's not going to go well. Do you understand?"

She absolutely doesn't believe they're just going to talk to her but she can play along until they actually try to hurt her, they're probably ready for her to just try to attack them right away. She scoots back from the door so she'll notice if they try to get close. "I understand, sir."

The one looking through the keyhole approves of her backing away from the door, since it does make it look like she'd not going to fight them.  They unlock it, and two men in uniforms come in, not getting too close.  "Well, hello.  I hear there's been some... really confusing and unfortunate... things going on with you, and I would really like to figure out why.  Can you tell me why you attacked the doctor?"

They looked at her rucksack and clothes, and her waterskin of all things, and the weird foreign-looking papers, and it sure does seem like something iffy is going on, rather than just a teenager making things up to get away from her parents. 

"He tried to steal my blood, and he said he just needed to look at it, and that he wasn't going to use it for Evil rituals or anything, and he promised he'd keep it right where I can see so I could be absolutely sure he wasn't doing anything like that, and then he tried to sneak it off into his weird chest."

Probably they're working with him so probably they already know all of that, but if they're working with him it's not like telling them a bunch of things they already know is going to to make anything worse.

That sure does sound concerning so far!  "What sorts of evil rituals were you worried about?  Have you ever seen any?"

"...The kind you do with someone's blood? So like, using it to summon a demon, boiling their blood inside them, binding their soul to something to make it your magic slave forever, I think there's some kinds of undead you can only make that way, that sort of thing. There's probably lots of kinds I've never even heard of. I've never seen anyone do any of those, I think you have to be a pretty powerful caster to make them work."

Actually, it's kind of weird that the doctor didn't just use magic to make her stop. Maybe he just works for a ritualist, or maybe there's some you can do even if you're not that strong.

The other policeman jumps in with: "Girl, what are you going on about??"  Really, weird satanist cults are one thing, but... what

The other one is still attempting to have a calm conversation.  "Have you ever seen any other kinds of evil rituals, or people's blood being taken for rituals, or anything like that?"

...She'd kind of been planning on pretending to be from a normal country, where people worship Erastil and the other Good and Neutral gods and definitely not Asmodeus, so they don't think she's an Asmodean and try to have her executed for that. Only now she's not sure how much a normal person in a normal country would know about Evil rituals — actually, she might already have said too much for her story, some of those are things she heard about from her mom. 

"Not that specifically. I've seen ... Evil people casting regular spells, and people casting regular spells that make people bleed, and the ritual for laying a corpse to rest so it doesn't rise, but that one's not Evil, and... I think Mending might technically be a ritual?" There, she's pretty sure that's vague enough that if she wants to claim the priest was an Erastilian or something she can.