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"Command HQ, this is Fireteam 2. Main power systems down in sub level. Backup and life support systems only. We've got lots of civilian casualties. It's a mess."
― Fireteam 2, reporting at the outbreak of the demon invasion  [src]

Fireteam 2 was a team of Marines stationed on Mars City in Doom 3.

When the demons invaded Mars, Fireteam 2 was in or around the Sub-Level Monorail at the time and were subsequently walled off from Marine HQ when it was destroyed. They reported power outages, along with lots of civilian casualties. Sergeant Kelly ordered the team leader to set up a Command Post at the nearest station. It is highly unlikely they survived, as they would've been cut-off due to the monorail being destroyed and they were not heard from after their report to Command HQ about the monorail's destruction.