Yeah, that's about what most people are doing! Nobody wants to get in the way of the - police? Soldiers? No, they're yelling STOP RUNNING and gesturing irresponsibly with their guns, so they're probably not soldiers. Anyway, everyone is trying to get inside or into buildings as the armed People With Suspiciously Advanced Technology rush onto the street, looking left and right for whoever it is they're looking for.

(The cart was blocking the view from street level, but there's a poster of a malevolent fellow in crudely-made black power lifter gear with a face-concealing helmet gazing down on the street, the helmet's eyeslit a pair of bulky security cameras, up against the wall. The writing on is in three different languages and incomprehensible.)

She isn't facing towards the camera - that will have to be enough.

The people running away are stymied when another bunch of identically equipped police/soldiers comes running in from the opposite direction. They look surprised, to the extent they have expressions to look at, to see the runners, but that doesn't stop them from having the cop's instinct to yell "STOP! HANDS IN THE AIR!" when they see them. Some of the running people will be brought down by energy bolts of some kind fired from the weapons, and others will dart into one of several alleys as the first group moves up to grab the unmoving bodies.

The pitch of the blasts means those rather low-quality phasers are set to stun, not to kill, so Lia doesn't move to intervene. If she does need to act she'll be able to use her own phaser now that it's clear this planet has encountered them - which means given the numbers it'll be an almost fair fight.

The first group is grabbing the bodies and handcuffing them. The second group is going through the crowds in pairs, asking them "have you seen anyone who looked like this?" showing them pictures, and glaring at them if they don't respond, which is the standard action.

The leader of the second group is glaring at the leader of first group and speaking very and firmly to him, though they're talking dialect the translator doesn't have much experience with, and fast enough that it may be difficult to pick up what they're saying.

Possibly she can get a glimpse of the pictures they're showing if she leans forward a bit?

The fact that the police(?) have internal conflicts is a point against this being Khan - Nova's police force was disciplined and had a clear chain of command. Though it would make sense if he was rather new to the planet and co-opting an existing system that worked less well.

Lia can! They're stock pictures of humans in Earth fleet uniforms, one male and one female.

... The police/soldier/armored guy showing the pictures at people will look over at Lia, meet her eyes, and freeze an instant.

She's stunned him before he can do anything else. Whoever these men are they've already opened fire on civilians and it's obvious she's next.

Firefight! The innocent bystanders panic and flee while the soldiers (none of whom have the training the United Earth Fleet can bring to bear) attempt to hit Lia with their huge bulky inefficient low-tech phasers. In most cases this is completely metaphorical and refers to the discharge of stun-blasts but one person next to her will, with reflexes wholly suitable to an experienced club-wielder who may never before have fired a gun in his life, attempt to smash Lia with the phaser's butt.

Avoiding phaser fire is not nearly so hard as other people make it out to be - you just need to avoid being where someone is about to fire. In a crowded market with stalls and incompetent opponents this is downright easy. She's managed to stun half a dozen of her opponents by the time club-wielder gets close enough to attempt melee. She uses the frankly excessive cover he provides to execute a wholly impractical backflip, shooting him as she lands. 

"Backup! Backup! We need backup!"

But they'll continue attempting to shoot her! More people will apparently join in on her side, dressed like anyone else until they out with weapons. They're carrying extremely crude weapons - swords and bows - which the body armor of the authority troops is significant protection against, especially after more of them show up.

(The actual innocent bystanders are doing the best job they can to get indoors or over to some other street, as fast as they possibly can).

Petra is no good in a fight. More importantly, she has no idea if she even wants to escape right now. Getting stunned seems like the easiest way to meet possibly-Khan. So when the opportunity presents itself she leans just a little too far to the left and into the open, getting hit by a phaser just as one of the soldiers rushes Lia.

Lia manages not to notice, too busy attempting a spinning kick while firing two phasers at once.

Petra will fall over while Lia delivers a devastating kick and hits with both phasers at once!

A young woman wielding a sword extremely well is going to stab a soldier/cop/person. "You're the one they're looking for?"