UK counterterrorism police have searched homes across London as they continue their investigation into the killing of Conservative MP Sir David Amess.
Amess, 69, was fatally stabbed as he met constituents on Friday at Belfairs Methodist Church in Leigh-on-Sea.
The main suspect, named as Ali Harbi Ali, 25, is being held at a London police station after being arrested under the Terrorism Act.
Detectives at Scotland Yard have until Friday to question Mr Ali, at which point they will be forced to charge or release him. The initial investigation is examining potential links to extremism.
Harbi Ali Kullane, reportedly a former adviser to the prime minister of Somalia, confirmed his British-born son had been arrested.
Speaking at his sister’s home in north London, Mr Kullane told The Sunday Times: “I’m feeling very traumatised. It’s not something that I expected or even dreamt of.”
It was reported that his son had been referred to the Prevent anti-radicalisation scheme several years ago, but was later removed.
Officers were seen entering a flat in north-west London in a search believed to be connected to the investigation.
Police arrived at a property in Lady Somerset Road and began carrying out searches late on Friday evening. They installed blue panels around the sides of the tent to prevent members of the public from being able to see inside.
“I’m completely, utterly shocked and surprised that police have started searches here", one resident said. “You just don’t expect it to be next door. This is a lovely road, it’s charming.”
The Daily Mail also reported a police presence at a home in Croydon, south London, where the suspect is believed to have spent much of his childhood.
Police and security services believe Ali acted alone. British media reports suggested he may have been "self-radicalised" and inspired by Al Shabab, the Al-Qaeda-linked extremists in Somalia.
Tributes continue for victim of fatal stabbing
Meanwhile, tributes have continued to flood in for the stalwart MP who had held a seat in the House of Commons since 1983.
Rayleigh and Wickford MP Mark Francois described his Conservative colleague Amess as his “oldest and best friend in politics” as he laid flowers outside the Belfairs Methodist church in Leigh-on-Sea.
Mr Francois was visibly emotional as he paid tribute to Amess, standing sombrely for a few moments in front of the floral tributes displayed outside the church where the Southend West MP was stabbed to death.
“He was the best bloke I ever knew,” Mr Francois said tearfully. He said he planned to say more about his friend in a tribute in the House of Commons this week.
Pope Francis also made reference to the killing as he described several recent violent incidents around the world as “a defeat for everyone”.
“Last week various attacks were carried out, for example in Norway, Afghanistan, England, which caused many deaths and injuries,” he said, during a public mass in St Peter’s Square, Vatican City on Sunday.
“I express my closeness to the families of the victims,” he said.
The Speaker of the House of Commons called for politics to be kinder after the death of his colleague and friend.
In an article for The Observer and The Mail on Sunday, Sir Lindsay Hoyle said he did not want to see an end to face-to-face meetings with constituents and urged the “hate” in politics to stop.
The fatal attack has raised questions about the safety of MPs and whether more security should be in place, or whether parliamentarians should conduct their surgeries entirely online.
“If anything positive is to come out of this awful latest tragedy it is that the quality of political discourse has to change," Sir Lindsay wrote.
“The conversation has to be kinder and based on respect.
“This incident has shown that there is unity across the political divide in support of democracy.
“The hate, which drives these attacks, has to end.”
The House of Commons has announced that most of the timetable for Monday will be scrapped to allow MPs to share their memories of Sir David before a church memorial service in the early evening.