Senior British officials say the two men detained for the gruesome murder of an off-duty British soldier on a London street had been identified earlier by security teams investigating suspected Islamist extremists.
The victim, a 25-year-old father named Lee Rigby who had served in Afghanistan, died at the scene. The two suspects were shot and wounded by police.
Media reports Thursday cited British Muslim hardliners and acquaintances who identified one of the suspects as 28-year-old Michael Adebolajo, of Nigerian descent.
Anjem Choudary, head of the banned British radical Islamist group al-Muhajiroun, said Adebolajo had regularly attended sermons by the group's Syrian-born founder Omar Bakri, who was banished from Britain in 2005.
VOA's Hausa Service confirmed that both suspects are British citizens who converted to Islam after being raised as Christians by their African immigrant families.
As the investigation progressed Thursday, British police said they had arrested a man and a woman on suspicion of conspiracy in connection with the case.
Rigby was rammed by a car and then hacked to death Wednesday afternoon near an army barracks in south London. Government officials said one of the attackers shouted "Allahu akbar" - "God is great" - as the soldier lay dying near him.
Prime Minister David Cameron said the killing was an appalling attack on Britain and a betrayal of Islam.
"This was not just an attack on Britain and on the British way of life. It was also a betrayal of Islam and of the Muslim communities who give so much to our country. There is nothing in Islam that justifies this truly dreadful act," Cameron said.
The prime minister also said Britain was "absolutely resolute in its stand against violent extremism and terror."
"We will defeat violent extremism by standing together, by backing our police and security services and above all by challenging the poisonous narrative of extremism," Cameron said.
The two suspects are under guard in a prison hospital.
Witnesses to the attack said the soldier was hacked to death with large butcher knives. British television broadcast a bystander's dramatic video showing a man identified as Adebolajo with blood-covered hands holding a cleaver and a knife.
He criticized the presence of British troops in foreign lands and justified the attack on religious grounds, saying to those around him, "the only reason we have done this is because Muslims are dying every day."
Adebolajo apologized to women and children who witnessed the bloodshed but said, "in our land, women have to see the same."
U.S. President Barack Obama condemned the attack, saying "the United States stands resolute with the United Kingdom, our ally and friend, against violent extremism and terror."
In signs of a backlash after the attack, more than 100 angry supporters of the English Defense League, a far-right street protest group, took to the streets late on Wednesday. Separately, two men were arrested in connection with separate attacks on mosques outside London. No one was hurt.
A police officer carries an evidence bag containing a knife near the scene of the killing of a British soldier in Woolwich, London, May 23, 2013.
Police officers search near the scene of the killing of a British soldier in Woolwich, London, May 23, 2013.
The mayor of London, Boris Johnson, speaks to police officers near the scene of the killing of a British soldier in Woolwich, London, May 23, 2013.
A wooden cross and a poppy, left as a tribute, are seen near the scene of the killing of a British soldier in Woolwich, London, May 23, 2013.
Tributes are seen near the scene of the killing of a British soldier in Woolwich, southeast London, May 23, 2013.
A police forensics officer investigates a crime scene where one man was killed in Woolwich, London, May 22, 2013.