Two men have been arrested in Birmingham and Manchester as part of the investigation into the Texas synagogue attack by British hostage-taker Malik Faisal Akram, Greater Manchester Police said.
Officers from Counter Terrorism Policing North West said they continue to support US authorities with their investigation into the events in Texas.
The two men remain in custody for questioning.
Malik Faisal Akram, 44, originally from Blackburn, was shot dead by law enforcement after taking hostages at the Congregation Beth Israel synagogue in Colleyville, Texas, on Saturday.
The Independent understands that the British man was known to MI5 but it is not known when he first came onto their radar, and he is not believed to have been considered an imminent security threat.
An audio recording obtained by the Jewish Chronicle revealed that the brother of the gunman urged him to surrender in their final phone call.
In the call, which gunman Malik Faisal Akram made to his family in Blackburn as the siege was going on, he told his brother he had “come to die”.
Experts believe the recording to be genuine. It reveals the efforts made by Akram's family to get him to surrender.
In the clip, his brother Gulbar tries repeatedly to talk him into surrendering, telling him that his hostages are innocent people and asking him to think about his children.
But the gunman tells his brother he has set his heart on dying and he wanted to “go down as a martyr”.
“I've only been here two weeks and I've got them all at gunpoint,” he said, later adding: “I'm coming back home in a body bag.”
Akram was also known to local police in Lancashire for previous criminal offences, and in 2001 had been banned from Blackburn Magistrates’ Court after ranting about the 9/11 terror attacks.
The gunman had links to the Blackburn, Burnage and Manchester areas, and flew into New York’s John F Kennedy airport around two weeks ago.
President Joe Biden said he spent at least one night in a homeless shelter and purchased the gun used in the attack “on the street”.
Counter Terror Policing North West arrest two teenagers in Manchester on Sunday night, in relation to the attack, but gave no further details. In total, four men in the UK have been arrested in connection to the incident.
Priti Patel said she had spoken to her US counterpart, Alejandro Mayorkas, and offered “the full support” of the UK police and security services in the investigation.
