Deactivate the missile launch while playing in Lente Missile Base
Every once in awhile a missile will attempt to launch from one of the silo's located in the center of the map. You will hear the alarms when it's beginning it's liftoff phase as notice the silo hatch doors are not open. Located in the second floor of the building on the south side of the map is a console which will turn green when you can deactivate the launch. It is the same room of the Tactician's respawn marker.

Video by Wozamil