At least five people have been killed and 25 injured after a gunman opened fire in west Cumbria.
A body, thought to be that of the suspect - taxi driver Derrick Bird - has been found in the Boot area of the Lake District.
The first fatality was in Whitehaven before the gunman drove south, apparently shooting people at random.
Prime Minister David Cameron told the House of Commons at least five people had been killed.
He said the country's thoughts were with those families who had lost loved ones.
Witnesses said the suspect drove through the town with a gun hanging out of his car window, before heading south through Gosforth and Seascale before turning inland.
A GP in the town of Seascale said he and a colleague had later certified two other people dead.
Dr Barrie Walker said: "The surgery was called and I went out. I've certified one of them dead. My colleague saw another," he said.
"At present there are two people dead and one seriously injured in Seascale. I know one of the victims. She was in the street.
Deputy Chief Constable Stuart Hyde said he believed Derrick Bird's body had been found
"The second person was on a bicycle and was shot on the bike."
BBC Look North Chief Reporter Chris Stewart said a farmer is also believed to have been killed in the Gosforth area.
After the shootings, detectives said 52-year-old Mr Bird drove to the central Lakes in a Citroen Picasso, then abandoned it in the Boot area.
Before the body was discovered people living nearby were urged to stay indoors for their own protection.
Helicopters and armed officers from other police forces were brought in to help apprehend the gunman.
Soon afterwards, Deputy Chief Constable Stuart Hyde said: "I can confirm that we've found a body in a wooded area near Boot which we believe to be Mr Bird, together with a firearm.
"A formal identification will be made later."
Nuclear plant shut Mr Hyde added: "Our focus now is to try and work out what has caused this and where Mr Bird has been over the last 24 hours and in particular the last few hours.
"I would plead to anyone who has seen him or has seen any of the incidents, please come forward, speak to us and help us piece together exactly was has happened in this very, very tragic set of circumstances.
"We have a number of crime scenes across the county, which are being staffed by police officers, and I would ask people to show a little bit of restraint and respect in regard to those scenes as we try and piece together exactly what has gone on."
.A major incident has been declared at West Cumberland Hospital, in Whitehaven, where the NHS said all routine operations had been cancelled.
The Accident and Emergency department at the Cumberland Infirmary in Carlisle is also on full incident stand-by, the hospital trust said.
The Sellafield nuclear reprocessing plant in west Cumbria closed its gates as a safety precaution and afternoon shift workers were being told to stay away, though the site has since reopened.
The Whitehaven victim, believed to be a colleague of 52-year-old Mr Bird, was killed at 1035 BST.
A local taxi firm boss, Glenda Pears, said: "We just don't know what's happened.
"The lad that's been killed was friends with him. They used to stand together having a craic on the rank.
"He was friends with everybody and used to stand and joke on Duke Street."
Sue Matthews, a telephonist at A2B Taxis in Whitehaven, said the Mr Bird was self-employed and lived alone. She described him as a "quiet fellow".
At the start of Prime Minister's Questions David Cameron expressed his shock at the events which had unfolded.
He said: "The government will do everything it possibly can to help the local community and those affected.
"When lives and communities are suddenly shattered in this way, our thoughts should be with all those caught up with these tragic events."
An emergency helpline has been opened for people concerned about the incident. Cumbria Police Casualty Bureau Line on 0800 096 009