KABUL, Afghanistan — A suicide bomber killed 14 people on Tuesday, including 10 foreigners, most of whom worked as flight crew members under contract with the United States government, officials said. The attack brought to at least 28 the number of deaths attributed to unrest sweeping the Muslim world as a result of a video parodying the Prophet Muhammad.

A spokesman for an Afghan insurgent group, Hezb-i-Islami, claimed responsibility for the bombing and said it was carried out by an 18-year-old woman “in response to the film insulting the Prophet Muhammad and Islam.”

The attack took place as word emerged that the American-led military coalition fighting the insurgents had sharply curtailed ground-level operations with the Afghan Army and police forces. The new limits were prompted by a spike in attacks on international troops by Afghan soldiers and police officers over the past six weeks. There was also fear that anger over the anti-Islam video could prompt such attacks, American officials said.