Not long after the destruction of the Death Star, the team of elite operatives was sent by Rebel Command to investigate strange signal being broadcasted from the outpost some distance away from the Rebel base. While command was almost sure that the outpost was a trap, it was decided that the signal should be cancelled as a first priority. Arriving at the outpost, the team attacked the outpost guards. As soon as the outside guards were defeated and the operatives approached outpost doors, the sirens started to wail. The transport pilot informed the operatives that multiple enemy squads are on the way, meanwhile the Imperials from within the outpost - stormtroopers and scout troopers operating E-Web repeaters - scrambled to organize second line of the defense. The fight was tough, but at the end the operatives prevailed over defenders, forcing remaining Imperials to retreat. As soon as all the transmitters have been smashed to bits and the signal ceased to be transmitted, the Rebels made their retreat to the transport. But as soon as transport lifted up to the air, the retreated Imperial soldiers - along with much more numerous fresh reinforcements - pour out of the forest - the distress beacon has done its job before it was destroyed. The operatives contacted Rebel command for advice and got their orders to return - with so many Imperial troops, there were little chance even for the elite operatives to prevail without heavy casulties. As it was later became known to Rebels, the distress beacon was activated by General Weiss who was stationed on the outpost and was able to escape with a help of arrived reinforcements.
"Aftermath", Campaign guide, page 4