British police said Wednesday they were holding two more men in connection with an armed hostage-taking at a Texas synagogue by a man from northwest England.
Malik Faisal Akram took four people, including a rabbi, hostage on January 15 at the synagogue in the small town of Colleyville.
He was shot dead by the FBI after a 10-hour siege during which he demanded the release of a female al-Qaida supporter imprisoned for attempted murder.
His hostages escaped unharmed.
In Texas, authorities have arrested the man suspected of selling Akram the semi-automatic handgun used in the attack.
In Britain, the Counter Terrorism Policing force for northwest England said it had arrested two men in the city of Manchester.
"They remain in custody for questioning," the force said in a statement.
The arrests bring to six the number of people held by British police over the hostage-taking, which renewed concern over an increase in anti-Semitic attacks on both sides of the Atlantic Ocean.
Three men are being questioned by police in Manchester, and another in the central English city of Birmingham.
Akram had planned the attack for at least two years. It was staged in an apparent bid to win the release of Pakistani woman Aafia Siddiqui, who has been jailed in Texas for the attempted murder of U.S. soldiers in Afghanistan.
Akram was reportedly investigated in 2020 by Britain's domestic security agency MI5 after he spent six months in Pakistan.
But the probe was ended after just more than a month and he was able to travel to the United States without being flagged as a risk.
Meanwhile, authorities in Texas announced the arrest of a man who they said sold Akram a semi-automatic Taurus G2C pistol two days before the synagogue attack.
The FBI said they had linked Henry "Michael" Williams to Akram through phone records, and that Williams confirmed that he had sold the gun to Akram.
Williams, 32, has a record of convictions on assault, weapons and drug-related charges.