KABUL, Afghanistan — Separate attacks in northern Afghanistan on Tuesday killed at least 15 Afghan troops, including 10 soldiers who died in an “insider attack” when a fellow soldier smuggled insurgents inside a checkpoint to kill his colleagues, officials said.

No group immediately claimed responsibility for the assaults. The so-called insider attacks – incidents when an Afghan soldier or policeman turns his gun on fellow troops – have been a serious problem in recent years.

In Tuesday’s assault, deputy provincial police chief in northern Zawzjan province, Abdul Hafiz Khashi, said that before dawn, a traitor allowed an unspecified number of insurgents into the compound at the checkpoint in Qush Tepa district, where they killed 10 soldiers. Khashi identified the soldier who enabled the attack as Mohammad Alim, saying he had obviously joined insurgents in the area.

The attackers and Alim fled the scene and security forces were pursuing them, he added.

Also Tuesday, a roadside bombing in northern Balkh province killed five police officers, including a district police chief, according to Sher Jan Durani, spokesman for the provincial police chief in Balkh.

The five were on patrol in a vehicle in Dawlat Abad district when their car struck the bomb. Three officers were wounded in the explosion.

Meanwhile, the new Taliban leader released a message ahead of the major Muslim holiday of Eid al- Adha, saying that for peace in Afghanistan, it is necessary to “end the occupation” of the country by all foreign forces – a reference to NATO troops.

Mullah Akhtar Mohammad Mansour also said that all existing military and security deals between the Kabul government and other countries must be revoked.

His message was likely an attempt by the newly appointed Mansour to reassure followers that he is keeping in tradition with his predecessor, the late Taliban leader Mullah Mohammad Omar, in releasing messages ahead of Eid al-Adha.