Detectives have named the police officer shot dead during a routine check of a stolen vehicle. Ian Broadhurst, 34, a married man, from Leeds, West Yorkshire, was gunned down in what police have described as an "appalling, dreadful attack".
His partner Neil Roper, 45, a father of two, from Wakefield, is in hospital after being injured in the attack.
Police are hunting the gunman, who was described as "exceptionally dangerous".
Detective Superintendent Chris Gregg, said the green Rover car that was commandeered by the gunman was found just after midnight on Springwood Lane, in the Oakwood area of Leeds.
It appears to be intact and has been sent for forensic examinations, he said.
"We are trying to find out exactly what happened in Dib Lane just after 4pm yesterday afternoon.
"We spoke to Neil Roper briefly before surgery yesterday."
A third patrol officer who had joined the two traffic officers suffered damage to his radar belt. It is unclear whether this was caused by a flying bullet, police said.
PA