An American military helicopter was filmed flying over an East Lancashire town earlier this week and locals were curious as to why.

A CV-22B Osprey helicopter was spotted over South Darwen on Monday (1 August) and the video was shared to social media page, Darwen Life.

One person asked: “Why are the US Marines flying over South Darwen?”

Another jokingly asked if they were lost.

A spokesperson for the 352 Special Operations Wing at RAF Mildenhall in Suffolk said the helicopters were circulating on Monday as part of the crew’s “routine training”.

They said: “We're grateful for the communities across the U.K. for their support - being here enables us to complete crucial day to day training.

“The 352d SOW constantly trains to further our ability to plan and execute specialised and contingency operations using advanced aircraft, tactics and air refuelling techniques.

“This aircraft has a one-of-a-kind combination of speed, range and operational flexibility, which makes it a versatile platform to enhance the efficiency of the war fighter.”

According to the US Air Force website, the CV-22B Osprey helicopter is a tiltrotor aircraft that combines the vertical takeoff, hover and vertical landing qualities of a helicopter with the long-range, fuel efficiency and speed characteristics of a turboprop aircraft.

Its mission is to conduct long-range infiltration, exfiltration and resupply missions for special operations forces.

The CV-22B is equipped with integrated threat countermeasures, terrain-following radar, forward-looking infrared sensor and other advanced avionics systems that allow it to operate at low altitude in adverse weather conditions and medium- to high-threat environments.