Thirteen Afghan army soldiers were killed in their sleep after two fellow soldiers poisoned them and later opened fire on them in Afghanistan’s embattled northern Kunduz province, officials said on Tuesday.

Gen. Dawlat Wazir, the spokesman for the ministry of defence said the ministry has launched an investigation into the incident.

“The two soldiers deserted the small base after killing their fellow troops in Zakhil area on the outskirts of Kunduz city, the capital of the province.

“We have sent a team to the area to investigate the matter,’’ Wazir said.

The Taliban claimed responsibility for the attack, but said the base was attacked by its troops and all weapons were seized.

A provincial council member from the province, Amruddin Wali, said the two soldiers were affiliated with the Taliban.

Wali noted that the defense ministry however has not clarified the soldiers’ affiliation with the insurgent group yet.