British police are questioning three North African men arrested in a raid that killed one policeman investigating suspected terrorists linked to the discovery of a deadly poison in London.
The murdered policeman, Stephen Oake, is being described as the first victim to die on British soil in the international war on terrorism.
He was fatally stabbed in the chest in a fight with one of three North African men arrested late Tuesday at an apartment in the city of Manchester in northern England.
Police say Detective Oake was part of team conducting a forensic investigation of the suspects to see if they possessed any dangerous chemical substances.
According to police, one of the suspects broke free from his police guard and grabbed a knife in the kitchen. Mr. Oake was stabbed as he tried to subdue the suspect. Four other policemen were injured.
The Manchester police chief constable, Michael Todd, told British radio the raid was connected to the discovery last week of traces of deadly ricin toxin in a north London apartment. "It's part of the ongoing fight against terrorism," he said. "And it was an intelligence-led operation, which led us to believe that there were some individuals that we needed to arrest to help in that fight against terrorism, and that's what this operation was about. And it was connected with the north London discovery, yes."
Mr. Todd said no toxin was found in the Manchester apartment, but the forensic investigation continues.
Four North African men have been charged with terrorism and chemical weapons offenses in the London ricin case.
One of the suspects arrested in Manchester was being transferred to London to undergo questioning by anti-terrorist officers. Manchester police have opened a murder case against the accused assailant in the killing of Mr. Oake.
The dead officer was 40-years-old, and he leaves behind a widow and three teenage children. Prime Minister Tony Blair has called the killing "an appalling tragedy, and wicked in the extreme."