Three other IRA members — Gerard Harte , Martin Harte and Brian Mullin — had been ambushed and killed by the SAS as they tried to kill an off-duty Ulster Defence Regiment soldier near Carrickmore , County Tyrone . British intelligence identified them as the perpetrators of the Ballygawley bus bombing , which killed eight British soldiers . After that bombing , all troops going on leave or returning from leave were ferried in and out of East Tyrone by helicopter . Another high-profile attack of the East Tyrone Brigade was carried out on 11 January 1990 near Augher , where a Gazelle helicopter was shot down
Ballygawley bus bombing
Ballygawley bus bombing
Clonoe ambush