U.K. Gunman: "Won't Stop Till I'm Dead"

British police from six separate departments joined forces Tuesday in the search for a man accused of shooting his ex-girlfriend, killing her new boyfriend and seriously wounding an officer.

Raoul Thomas Moat, 37, was released from prison last week after serving a sentence for assault.

In a letter allegedly sent from Moat to authorities in the Northumbria region where he has disappeared, the suspected killer "declares war" on the police and says he "won't stop till I'm dead."

His former girlfriend, Samantha Stobbart, 22, was shot in Gateshead, northeast England, on Saturday. Her new boyfriend, Charles Brown, 29, was killed outside the same house, police said. Constable David Rathband, 42, was shot a few miles away in Newcastle early Sunday. He remains hospitalized in critical but stable condition.

Police surrounded a home in Gateshead Tuesday morning and launched what appeared to be a search operation. Live television coverage of the ongoing operation showed unarmed officers and members of the public milling about the scene - making it seem unlikely the police had Moat holed up at the residence.

In another development, a fish and chips carry-out restaurant in northern England was robbed at gunpoint Monday evening by a man strongly resembling Moat. Police would not say definitively if they suspected a link to the shooter, but they would not rule it out.

Authorities have requested "additional firearms trained officers from a number of other forces" as they search for Moat, Northumbria Police said.

Stobbart was initially hospitalized in critical condition, but has since improved, authorities said, without specifying her new condition.

Stobbart, who has a baby with Moat, issued an appeal through police for the former bouncer to give himself up.

Det. Chief Supt. Neil Adamson, the police officer leading the manhunt for Moat, also urged him to surrender.

"Mr. Moat, we are aware that you have a number of issues and grievances," Adamson said. "We want to understand your position and I want you to realize that you do have a future. We can only help you with this if you make contact with us directly."

The shootings occurred a month after a man went on a killing spree in England on June 2, when taxi driver Derrick Bird killed a dozen people and wounded 11 others before committing suicide.

Unlike those attacks, many of which were random, police hunting for Moat said they don't believe he poses a danger to the general public, because he has "specific grievances against certain individuals and groups." But some people have been given police protection, authorities said.

One of those grudges appeared to be against the police, which may have stemmed from the fact that Stobbart told Moat that she was dating a police officer because she was scared of Moat, Adamson said as he read out her statement.

"We've spoken to Sam and she has asked us to say the following to you: 'Please give yourself up. If you still love me and our baby you would not be doing this any more,'" Adamson read. "Sam also said: 'When you came out of jail I told you I was seeing a police officer. I said this because I was frightened. I have not been seeing a police officer.'"

In the letter allegedly from Moat, which was published Tuesday by The Sun newspaper, the suspect says the public should not fear him.

"The public need not fear me but the police should as I won't stop till I'm dead," the letter reads. "I'm a killer and a maniac but I ain't no coward."