It seems that one of Shane's men has been cornered by the Akurans. Fetch insists on protecting them and grabs onto a power source nearby, which seems to make her shots a little bit explosive once they hit an Akuran. Take out all the Akurans to rescue Shane's man and Shane will call and say another has been cornered.
After rescuing the second guy, Fetch comes up with a plan, so head to the third, and final, spot. Here, the Akurans will be concentrating on you, and will be coming from a few different directions. That means you need to pay attention, and also use L3 to help pinpoint their locations. Make sure you keep an eye out for snipers, which make their debut in this mission.
The enemies will be on the street ahead of you, but also on the rooftops to the left and right. Once you finish off the last enemy, the mission will be over.