4 Afghan guards killed in blast

KABUL — The government says a roadside blast has killed four Afghan guards in the south of the country.

An Interior Ministry statement says the explosion hit the guards’ vehicle in Helmand province on Thursday. The victims worked for a private security company.

Thousands of U.S. Marines are conducting an anti-Taliban offensive in Helmand province, one of the centers of the Taliban insurgency. British troops are also fighting militants there.

Insurgents have dramatically increased their use of roadside bombs this year.