A number of people are believed to have been killed after two US Army helicopters crashed in Kentucky.

The state’s Governor, Andy Beshear, said it was “tough news” with “early reports of a helicopter crash and fatalities are expected”.

Local news reports say the incident happened at about 21:35 local time and as many as nine people may have been killed.

Local military confirmed their helicopters were involved in the crash.

It happened in the Trigg County area, close to the large Fort Campbell military base. Fort Campbell spokesperson said two HH60 Blackhawk helicopters had crashed during “a routine training mission”.

“The status of the crew members are unknown at this time,” they said. “The command is currently focused on caring for the service members and their families.” They added the incident was under investigation and more information would be released as it becomes available.

The Fort Campbell military base is located a short distance from Trigg County.

The helicopters involved are from the 101st Airborne Division, which is the only air assault division in the US Army and has been sent to conflict zones internationally.