Complex sentence: The unit's creation stems from the need to provide infantry support to the special forces, which became evident after the Battle of Tora Bora during which two SAS sabre squadrons assaulted the al-Qaeda cave complex.
Split into simpler sentences: The unit's creation stems from the need to provide infantry support to the special forces, which became evident after the Battle of Tora Bora. During the battle, two SAS sabre squadrons assaulted the al-Qaeda cave complex.