Northern Ireland bomb witness: 'I heard an awful bang'
2 April 2011 Last updated at 21:25 BST
A 25-year-old, police officer, Ronan Kerr, was killed when a bomb exploded under his car in Omagh, County Tyrone.
The device exploded under the vehicle outside his home in Highfield Close, just before 1600 BST on Saturday.
Charlie Dolan said he heard the device go off and rushed with other neighbours to the scene to see if he could help.