Afghan police officers being killed in their sleep

— all slain in their sleep, at the hands of those close to them.

Early Thursday morning, an Afghan policeman unlocked the door of the post where he was stationed in Oruzgan province and let in his friends from the Taliban, who with knives and guns helped him kill four and wound eight of his sleeping colleagues.

On Sunday, a local police commander in the remote northern province of Jawzjan shot to death, in their beds, five of the men under his command, and fled to join the Taliban. And on Dec. 18, a teenager apparently being kept for sexual purposes by an Afghan Border Police commander in southern Kandahar province drugged the commander and the other 10 policemen at the post to put them to sleep, and then he shot them all; eight died and three survived with wounds.

In the crisis that has risen in the past year over insider killings, when Afghan security forces turn on their allies, the toll has been even heavier for the Afghans themselves — at least 86 in a count by the New York Times this year.

Unlike most insider attacks against foreign forces, known as “greenon-blue” killings, most of the attacks between Afghans, “green on green,” have been clear cases of either infiltration by Taliban insurgents or turncoat attacks.

The wave of killings over the past year has policemen all over Afghanistan watching what they eat, and sleeping uneasily.