A Blackburn gunman who took hostages at a Texas synagogue was previously investigated by MI5.

Malik Faisal Akram was shot dead when the FBI stormed Congregation Beth Israel synagogue in Colleyville on Saturday night after a 10-hour seige in which all four hostages were freed unharmed.

The 44-year-old was investigated by the security services in 2020 but deemed not to be a credible threat to national security at the time, official sources confirmed.

Akram became a subject of interest (SOI) for MI5 when he was investigated in 2020 but was assessed not to pose a credible threat to national security so was downgraded and marked a “closed” SOI.

He was not subject to a live investigation when he travelled to the US it is understood.

MI5 investigates around 3,000 SOIs and has about 600 live investigations at any one time. There are also around 40,000 “closed” SOIs – those who have been looked into previously. Significant numbers of SOIs are overseas.

The security service only investigates SOIs when it believes the individual may pose a threat. This threat will be ranked by priority and resources will be dedicated to them depending on the level of threat they are judged to pose.

As soon as they are no longer deemed to pose a threat, they are downgraded and placed on the closed list.

This does not suggest they will never pose a threat again, but rather than their current level of threat is not considered sufficient to prioritise allocating resources to them. This situation could change at any time and be re-assessed.

It is not yet clear how Akram, who had a criminal record in the UK, was able to travel to the US two weeks ago.

US officials believe Akram had a visa, arrived at John F Kennedy International Airport in New York and bought the handgun used in the incident.

According to reports, he stayed at a homeless shelter and is believed to have bought a gun on the street before taking four people hostage at the synagogue on Saturday, one of whom was released after around six hours.

At one point he demanded the release of Pakistani neuroscientist Aafia Siddiqui, who was convicted of trying to kill US army officers in Afghanistan, and is in prison in Texas.

The FBI in Dallas had earlier said there was nothing to suggest a wider terror plot.