A pedestrian has suffered head injuries after being hit by a motorbike in Bolton .
Police were called to reports of the crash in De Havilland Way, close to Middlebrook Retail and Leisure Park in Horwich, at about 4.30pm.
The pedestrian's injuries are understood to be serious.
An ambulance was called to the scene, while eyewitnesses have also reported seeing an air ambulance land in the area close to the University of Bolton Stadium.
The incident is causing major delays on the surrounding road network, with De Havilland Way reportedly closed in the direction of junction six of the M61.
Motorists are being advised to avoid the area, if possible.
A spokesperson for Greater Manchester Police said: "We were called to De Havilland Way at about 4.30pm to a collision between a motorcycle and a pedestrian.
"An ambulance has been called. The pedestrian looks to have suffered a head injury."
Middlebrook Retail & Leisure Park posted on Facebook: "There has been an accident on De Havilland way - the road is currently closed heading towards the M61 after the spirit of sport roundabout.
"Traffic is building up in the area.
"All traffic is being directed through Horwich and Chorley New Road.
"If you do not need to travel please don't as this will only add to the congestion.
"The air ambulance is currently in attendance."
