ABC News - Up to 14 people, including four American contractors, were kidnapped in an ambush of a convoy near the southern Iraq city of Nasiriyah on Thursday, ABC News reported, citing defense officials.

"We can confirm that an incident happened in Nasiriyah that resulted in kidnappings," said Sgt. Matthew Roe, a U.S. military spokesman in Baghdad.

The spokesman provided no additional details, adding, "We are working on getting further information on that right now."

ABC News, citing military officials, said a convoy run by a Kuwaiti-based company called Crescent Security Group was stopped at what looked like an Iraqi police checkpoint.

Initial reports said 19 trucks were seized and about 14 people detained, including four Americans, ABC reported.

The report said it was not clear whether the checkpoint was operated by actual Iraqi police or by a Shi'ite militia.