KABUL, Afghanistan — The U.S. military is investigating allegations that a "small number" of U.S. soldiers were responsible for the unlawful deaths of as many as three Afghan civilians.

A U.S. statement this morning said the allegations also included illegal drug use, assault and conspiracy. No charges have been filed, but one soldier was placed in pretrial confinement.

The Army's Criminal Investigation Command began the investigation after receiving credible information from the soldiers' unit earlier this month.