KABUL, Afghanistan (AP) — Attackers killed five Afghan policemen escorting a U.N. convoy on the main highway heading east from Kabul before escaping, the United Nations Assistance Mission in Afghanistan said on Thursday.

No one immediately claimed responsibility for the attack, but Afghanistan has seen a nationwide spike in bombings, targeted killings, and violence on the battlefield as peace negotiations in Qatar between the Taliban and the Afghan government have stalled.

UNAMA said the U.N. family in Afghanistan mourns the loss of the Directorate of Protection Service troops in the Surobi district, some 60 kilometers (37 miles) east of the capital.

“No U.N. personnel were hurt, or vehicle effected in an attack which hit a DPS directorate of protection forces vehicle that was escorting a UN convoy,” it said in a tweet.

The U.N. convey came under fire in the Tang-e Habreshim area, killing a driver whose vehicle then veered off the road into a river, leaving four other occupants dead as well, said an official who was not authorized to speak with media.

The Islamic State group’s local affiliate has claimed responsibility for some recent attacks, but many go unclaimed. The government often blames the Taliban, but the group mostly denies responsibility.

In a separate incident in northern Faryab province, unknown gunmen shot and wounded Qatbuddin Kohi, a local reporter and journalist union leader, said provincial police chief spokesman Karim Yuresh.

Kohi is in good condition, he said, adding that police have launched an investigation. Afghanistan has also seen a wave of attacks in recent months against journalists, human rights activists and civil society members. The international press freedom group Reporters Without Borders has called the country one of the world’s deadliest for journalists.