A suicide bomber on a motorcycle attacked NATO troops in Afghanistan, officials said Monday.

NATO confirmed there was an incident near Bagram Airfield but declined to comment further on whether there were any casualties.

“We can confirm there has been a vehicle-borne improvised explosive device attack in the vicinity of Bagram Air Field,” the coalition said in a statement. “At this time, the incident is under investigation.”

Parwan provincial police chief Gen. Zaman Mamozai told NBC News that a suicide bomber on a motorcycle attacked a convoy of Afghan and Western forces at around 1 p.m. local time. He said he was not aware of any casualties among the Afghan or Western forces.

The Taliban posted a message on Twitter claiming responsibility for the attack.

An attack near Bagram Airfield in September killed one NATO service member.