Three more people were arrested Saturday in connection with last week's grisly killing of British soldier Lee Rigby, police said.
The men were being held on suspicion of conspiracy to commit murder, the Metropolitan Police said in a statement.
Police did not detail how they were allegedly tied to the killing, nor did they release their identities, saying only that the men -- ages 21, 24 and 28 -- were arrested by detectives from the Counter Terrorism Command and taken to a south London police station.
Police said a Taser was used on two of the men, who "did not require hospital treatment."
Police also were carrying out search warrants at four residential addresses associated with the three men, the statement said.
The brutal slaying Wednesday of Rigby near the Royal Artillery Barracks in Woolwich, a working-class neighborhood in southeast London, shocked people across the United Kingdom.
One of the two suspects arrested at the scene approached a man filming the scene in the Woolwich neighborhood and suggested that Rigby had been targeted only "because Muslims are dying daily" at the hands of British troops such as him.
"We must fight them as they fight us. An eye for an eye and a tooth for a tooth," he said in the video aired by CNN affiliate ITN.
Britain's armed forces have served in Iraq and Afghanistan. All its combat troops are due to leave Afghanistan by the end of 2014.
Another man, 29, who was arrested Thursday on suspicion of conspiracy to murder in connection with the Woolwich investigation was released on bail, police said Saturday.
British counterterrorism police arrested a man who said he was a friend of a suspect in the Woolwich soldier killing, after he gave an interview to the BBC on Friday night, the British broadcaster said.
The man, Abu Nusaybah, was arrested on suspected terrorism offenses after telling on air how his friend had been approached by Britain's domestic intelligence service, known as MI5, according to the broadcaster.
A BBC staffer, who did not want to be named, told CNN that police were inside the BBC Broadcasting House building in central London waiting for the interview to conclude before they made the arrest.
Friends, acquaintances and British media identified 28-year-old Michael Adebolajo, a British national of Nigerian descent, as the suspect seen in a gory video from the scene of the Woolwich killing.
Authorities have not identified that individual or the 22-year-old man seized with him at the scene by armed police. Both suspects were shot and remain in hospital.
A Scotland Yard spokesman told CNN the arrest at the BBC was not connected to the murder investigation in Woolwich.
The attack has sparked concerns that anti-Muslim sentiment may flare up in communities angered by the killing of the soldier, drummer Lee Rigby.
Members of a far-right group, the English Defence League, called for Muslims to leave Britain as they rallied in Newcastle, northern England, on Saturday. The protest march came only hours after a group that monitors anti-Muslim abuse told CNN of a big spike in reported incidents in the past two days.
'Changed and withdrawn'
In the interview with BBC's "Newsnight," Abu Nusaybah said MI5 had approached Adebolajo in the past year, asking if he wanted to work for them.
Adebolajo rejected the approach, according to his friend.
Abu Nusaybah said the contact from MI5 occurred last year after Adebolajo returned from a visit to Kenya during which he was detained by security forces.
Adebolajo told his friend that he was physically assaulted and sexually threatened during his detention.
CNN is working to independently verify the allegations made by Abu Nusaybah about his friend's treatment in detention.