Two suspects are detained in Manchester as part of the investigation into the attack in Texas.
Two men have been arrested as part of an investigation into an attack on a Texas synagogue which saw a gunman take four people hostage.
Malik Faisal Akram, 44, from Blackburn in Lancashire, was shot dead by the FBI after a 10-hour standoff in the US on 15 January.
Greater Manchester Police said two men were arrested in Manchester earlier.
Two other men arrested in Birmingham and Manchester on 20 January have been released with no further action.
The force said officers from Counter Terrorism Policing North West were continuing with their investigation and working closely with US law enforcement.
The siege began at about 11:00 local time (17:00 GMT) when police were called to the Congregation Beth Israel synagogue in Colleyville, near Dallas.
Akram had entered the place of worship during a morning service by pretending to be homeless, before pulling out a gun.
One hostage was released after six hours, while the other three – including the synagogue’s rabbi – escaped several hours later.
During the standoff Akram was heard demanding the release of Aafia Siddiqui, a Pakistani neuroscientist who is serving an 86-year prison sentence in nearby Fort Worth, Texas, over attempts to kill US soldiers in Afghanistan.
Siddiqui has distanced herself from his actions, issuing a statement through a lawyer.
Image source, EPA
Akram is thought to have arrived in the US via New York’s JFK International Airport two weeks prior, according to police sources.
He is believed to have bought weapons used in the incident “on the street” after his arrival.
Akram had been on the British security service’s watchlist as a “subject of interest” in 2020 and was investigated in the second half of that year.
But by 2021 Akram, who had a criminal record in the UK, had moved from the active list to the “former subject of interest” list and was no longer considered a threat.
In a now deleted statement published on the Blackburn Muslim Community’s Facebook page, Akram’s brother Gulbar said his sibling had been suffering from mental health issues.
Friends of Akram in Blackburn said his mental health had been getting worse and expressed surprise that he had been able to travel to the US.
