London - Three people arrested over the grisly murder of a soldier in London have been released on bail, British police said on Monday, while the two main suspects remain in hospital.
Detectives are trawling through CCTV footage, social media, forensic evidence and intelligence reports relating to the hacking to death of 25-year-old Lee Rigby near a barracks in Woolwich by two Islamists.
They have arrested a total of nine people, but have yet to formally interview the prime suspects because of the men's injuries sustained in police gunfire at the scene.
Michael Adebolajo, aged 28, and Michael Adebowale, aged 22, both British Muslim converts from Nigerian Christian families, remain under armed guard at separate London hospitals.
They are "in a stable condition and will be formally interviewed when it is possible to do so", Scotland Yard said on Monday.
Three men arrested on Saturday on suspicion of conspiracy to murder have been bailed. Another man arrested for the same offence on Thursday was also bailed, while another remains in custody.
Two women arrested last week were released without charge.
"This remains an ongoing investigation, focussed upon public safety and identifying any others that may be involved," said Stuart Osborne, Scotland Yard's head of counter-terrorism.
"The investigation is progressing well, but there is still a lot more work to be done."
Separately, police won judicial approval on Sunday to question a 31-year-old man for another five days on suspicion of the commission, preparation or instigation of acts of terrorism.
Abu Nasaybah was arrested on BBC premises late on Friday shortly after giving an interview about his friendship with Adebolajo, in which he claimed MI5 had tried to recruit the murder suspect.
Last week's brutal attack by two men spouting Islamist rhetoric has raised concerns about a backlash against Muslim communities.
Teens held for mosque attack
Despite calls for calm from Prime Minister David Cameron and Muslim and Christian leaders, one charity said it had recorded a huge spike in anti-Muslim incidents, while there have also been a number of attacks on mosques in recent days.
An Islamic cultural centre in Grimsby in northeast England was hit by petrol bombs on Sunday night, although police said it was "too early to speculate" on why the fire was started.
Two people have been arrested over the attack, which did not result in any injuries, and police said they were monitoring messages posted on social networking sites that "appear to be an attempt to incite trouble".
Eleven teenagers aged 16 or 17 were arrested for attacking the Grimsby mosque and cars parked outside on Thursday night after a party nearby got out of control, police said.