Investigations into what made a taxi driver embark on a rampage that left 12 people dead and 11 hurt in Cumbria in Britain may centre on a family row.
Derrick Bird, 52, went on a three-hour shooting spree which began in Whitehaven and ended when he turned the gun on himself in woods near the village of Boot, in northwest England.
The BBC says it is being reported Mr Bird, a divorced father of two and a grandfather, may have been involved in a dispute with his family over a will.
British newspapers are reporting his first victim was his twin brother David, then the family solicitor, followed by a taxi driver.
Other speculation in British media is that a row with other drivers the previous day over stealing fares sparked the attacks.
Mr Bird killed another driver at a taxi rank in the seaside town of Whitehaven, then witnesses say he drove through the town with a gun hanging out the car window, before heading south, randomly shooting more people as he went.
Three and a half hours later, he killed himself. A shotgun and a rifle with a telescopic sight were found nearby.
Before the body was discovered, people were urged to stay indoors for their own protection.
Police say officers are attending 30 different crime scenes. They say their investigation will cover Mr Bird's history, his access to guns, and his motives.
Cumbria deputy chief constable Stuart Hyde described the shootings as "terrifying and horrific".
Shock at events
Churches in the area opened their doors to people looking for a place to reflect.
The Rector of Whitehaven, Reverend John Bannister says a special outdoor service was being organised to try to help the community come to terms with what happened.
It was the worst mass shooting in Britain for 14 years.
In Parliament, Prime Minister David Cameron expressed his shock at the events.
He said the government would do everything it possibly can to help the community and those affected.
The Queen says she is deeply shocked by the shootings and shares the country's grief and horror.
Britain has some of the strictest gun laws in the world, and such large-scale attacks are rare. The last on a similar scale was in Scotland 14 years ago.