WASHINGTON (AP) — A series of “insider attacks” against U.S. and allied troops by Afghan forces are an attempt by the Taliban to drive a wedge between coalition and Afghan troops, a senior officer said Wednesday. But he said that while Western troops are now warier of Afghan partners, they are determined to avoid a full breakdown in trust.

Australian Brig. Gen. Roger Noble, deputy to the alliance’s operations chief, acknowledged in a teleconference from Kabul that the attacks, which have killed 51 coalition troops this year, are upsetting the troops. He said he visited Australian troops at a base where an insider attack killed three Australians on Aug. 29.