John Onyenaychi will serve minimum of 25 years after conviction for attempted murder of two officers in London last December A knifeman described as one of the most dangerous men in Britain has been jailed for life for trying to kill two police officers. John Onyenaychi cut Paul Madden's throat and then lashed out with his knife at other officers who tried to restrain him in Ealing, west London, last December, the Old Bailey heard. Madden was saved by a retired heart surgeon, Samad Tadjkarimi, who was out Christmas shopping. The 23-year-old officer was taken to hospital by helicopter and received emergency surgery for injuries to his neck, throat and face. He was left with permanent scarring. A police community support officer Piotr Dolata, 27, needed 12 stitches to a knife wound to his head, and another PCSO, Steven Constable, was slashed twice but was saved from serious injury by his jacket. Onyenaychi, 30, of Stratford, east London, was found guilty of two counts of attempted murder, causing grievous bodily harm with intent, robbery and attempting to cause grievous bodily harm. He was ordered to serve a minimum of 25 years for the attack on Madden, and given a second life term with a concurrent minimum of 20 years for attempting to murder Dolata. Tadjkarimi, who had retired from Harefield hospital three weeks before the incident, said: "It's my duty, I guess. I'm sure anyone in my profession would do the same. It's very humbling that my intervention perhaps contributed to the outcome of possibly saving [Madden's] life ? a very brave young officer." Crime London guardian.co.uk © 2011 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds