BOOT England, (AFP) A gunman killed at least 12 people after going on a rampage in a popular tourist area in northwest England on Wednesday, before apparently turning the gun on himself, police said. Some 25 people were injured when Derrick Bird, a 52-year-old taxi driver, spent nearly four hours driving through the Lake District, reportedly shooting at people from his car window. Three of the injured were in a critical condition, police said. We can... confirm that from our current indications that 12 people have lost their lives, plus Derrick Bird (the gunman), said Deputy Chief Constable Stuart Hyde. During the rampage police warned frightened local residents and tourists to stay indoors for their own protection. What is thought to be Birds body was eventually found in woods, along with a gun, near the town of Boot. People in the normally sleepy Lake District - popular with hikers for its spectacular mountain views, plus fans of childrens author Beatrix Potter - voiced deep shock at what had happened. You would think he was a very placid, very quiet man, kept himself to himself, so I do believe something pushed him over the edge, John Kane, a local resident who knew Bird, told the BBC. A local doctor, Barrie Walker, told of blood flowing in the streets as he attended to victims, while the local ambulance service said it received 51 emergency calls as the tragedy unfolded. One resident, Gary Toomey, recounted how he found one victim bleeding on the doorstep of his home. I saw a car screeching off and a man saying 'help me. He was bleeding heavily from the side of his face, he told local media. British Prime Minister David Cameron expressed his condolences in a statement at the start of his first weekly grilling in parliament since taking office, saying he was alarmed and shocked by the shootings. Deputy Chief Constable Hyde, who is leading the investigation, said they did not know what caused Bird to strike. Our focus now is to try and work out what has caused this and where Bird has been over the last 24 hours, he said. 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. Britain has tight controls on gun ownership introduced after two previous mass shootings in recent years. In 1987, 27-year-old Michael Ryan shot 14 people dead in the town of Hungerford in Berkshire, southern England. And in 1996, 16 children aged five and six plus their teacher were shot dead in the gym of a primary school in Dunblane, central Scotland, by 43-year-old Thomas Hamilton.