TEHRAN, Iran – A bomb explosion killed at least 18 members of Iran’s elite Revolutionary Guards in southeastern Iran, the state-run news agency reported today.

A passenger car loaded with explosives stopped in front of their bus near Zahedan, the capital of Sistan-Baluchestan Province, the official Islamic Republic News Agency reported.

“This blind terrorist operation led to the martyrdom of 18,” IRNA quoted a Guards commander, Qasem Rezaei, as saying.

There was no immediate claim of responsibility.

The explosion occurred around 6:30 a.m. local time in Ahmadabad district on the outskirts of Zahedan, IRNA said.

The passenger car stopped in the middle of the road, forcing the bus loaded with Guards to stop. The car’s occupants fled on motorbikes seconds before it exploded, IRNA said.

Zahedan and its surroundings, which lie near Iran’s borders with Pakistan and Afghanistan, have been the scene of clashes between police and drug smugglers.