WASHINGTON (Reuters) - An explosion at an entry control point at Bagram airfield near the Afghan capital Kabul caused a small number of casualties, the U.S. military said on Wednesday.

“An explosion occurred outside an entry control point at Bagram Airfield at 5:38 p.m. local time today,” a statement said.

“The explosion resulted in a small number of casualties,” it said, adding that the airfield was secure and the incident was being investigated.