Image caption
The crash happened at about 13:35 BST near Great Yarmouth Yacht Station
A boat has crashed in Norfolk, with one person believed to have been knocked into a river.
Police said officers were told there was a woman in the water at North Quay, Great Yarmouth, following the crash at 13:35 BST.
It is understood the woman fell into the River Bure after the boat hit a wall.
Emergency services have described the incident - near the town's yacht station - as "very serious".
Four fire engines, four ambulances, RNLI lifeboat, HM Coastguard patrol officers and police are at the scene.
Initial reports said that two boats had collided, but it was later confirmed to be just one vessel.
Image caption The coastguard described the incident as "very serious" Image caption The fire service, ambulances, RNLI lifeboat, HM Coastguard patrol officers and police are at the sceneFind BBC News: East of England on Facebook, Instagram and Twitter. If you have a story suggestion email eastofenglandnews@bbc.co.uk