A CONTROLLED explosion is set to take place this afternoon in the Booker area, following the discovery of an “unexploded shell” in Wycombe Marsh today.

Police cordoned off Chequers Avenue, which leads to a building site, after contractors discovered the suspected explosive this morning.

Builders working on a site in Sierra Road discovered a device, believed to be a Second World War hand grenade, shortly before 10am.

Police have confirmed the shell will now be moved to a safe location in the area of Booker Airfield so that a controlled explosion can take place.

Workers have now returned to the construction site, which was evacuated this morning.