LONDON — Three men were being held in custody Sunday on suspicion of conspiracy to murder the British soldier hacked to death in a London street in an Islamist attack.

Two men aged 28 an 24 were arrested at a home in southeast London Saturday, with police firing a Taser electric stun gun on the older suspect, and on a 21-year-old man they arrested in a street around 1.5 km from the murder scene.

Britain is dealing with the aftermath of a grisly murder which was the first fatal terror attack in the kingdom since the 2005 London bombings. Prime Minister David Cameron is launching a new task force to tackle extremism and radicalization, his Downing Street office said.

Meanwhile an inter-faith group reported a large spike in anti-Muslim incidents.

Drummer Lee Rigby, 25, who survived a tour of duty in Afghanistan, was butchered in broad daylight Wednesday outside the Royal Artillery Barracks in Woolwich, southeast London.

Michael Adebolajo, 28, and 22-year-old Michael Adebowale remain in a stable condition after being shot by police at the scene of the killing. They have both been arrested on suspicion of murder and are under armed guard in separate hospitals.

The three men arrested Saturday on suspicion of conspiracy to murder were all held by detectives from the Counter Terrorism Command supported by specialist firearms officers. Officers were also searching four residential addresses in southeast London.

Cameron’s new counter-terror task force will include key cabinet ministers and bring in police and security chiefs when needed.

It will focus on radical preachers who target potential recruits in jails, schools, colleges and mosques. It was also to monitor trends in radicalization and tackle "poisonous narratives".

Downing Street said the group would seek practical measures rather than getting bogged down in theoretical debates about Britishness and cultural values.

Writing in The Sunday Telegraph newspaper, Communities Secretary Eric Pickles urged politicians, judges and the public sector to take a robust line against extremists.

Meanwhile Britain’s intelligence agencies were facing scrutiny following claims that the MI5 domestic security service had tried to recruit one of the two murder suspects.

Both men were known to the intelligence services and Adebolajo had links to the banned Al-Muhajiroun movement, but ministers and security experts have warned of the difficulty in keeping track of everybody with extreme views.

Both were brought up by Nigerian Christians and converted to Islam in their teens, and recently were seen handing out extremist literature in the streets — to the concern of their families.

Newsapapers carried pictures of Adebolajo in court in the Kenyan city of Mombasa in November 2010. — AFP