The ringleader of the Rochdale grooming gang, Shabir Ahmed, has been released from prison while the UK government keeps looking for a way to deport him.

Ahmed, 73, known as “Daddy” by his victims, held dual British and Pakistani citizenship at the time of his conviction. He was jailed for 22 years in August 2012 for a string of child sexual offences including rape. This week his victims were told he would be released on licence and despite earlier promises, could not be deported due to a 55-year-old law.

Ahmed held dual British and Pakistani citizenship at the time of his conviction. His British citizenship was stripped by the courts after he was jailed and it was expected he would be deported once his sentence ended.

Keir Starmer has since asked the home secretary to review the case amid calls for the law to be changed to allow Ahmed’s removal from the country. Ahmed is now in 24-hour staffed accommodation, wearing a GPS electronic tag.

British media reports have stated that Ahmed cannot be deported back to Pakistan due to provisions under the Immigration Act 1971.

The Immigration Act 1971 is the law that governs who can enter, stay in, and be removed from the UK. Under its provisions, a Commonwealth citizen who arrived in Britain before 1973 and had already been living in the country for five years is protected from deportation.

Ahmed, who moved to the UK in the late 1960s, falls under its protection- officials have said that his removal is currently barred despite his conviction. The Home Office has said that the same provisions “protected many individuals caught up in the Windrush crisis.”

A No 10 spokeswoman said that Ahmed’s crimes were at the heart of the grooming gangs scandal, calling it one of the darkest moments in the country’s history. She added that he would be on the sex offenders register for life, ordered to stay away from his victims and banned from contacting any child or young person.

“His every movement will be tracked, and forced to wear an electronic tag,” she said.

Conservative leader Kemi Badenoch said that her party would attempt to amend the government’s Immigration and Asylum Bill “to close the loophole so that this man can be deported immediately.”

Andy Burnham, expected to take over as Labour leader and prime minister in the coming weeks, wrote on social media that he wanted “this vile criminal out of the country” and that victims must come first. He said he would ask the home and foreign secretaries to review all possible options, adding that nothing should be off the table.

Labour MP Jim McMahon, who represents a constituency in Oldham where some of the abuse occurred, told an international media outlet that the 1971 act was meant to protect Commonwealth citizens who came to the UK for a better life and contributed to the country.

“It was not designed to give a free pass to a child rapist,” he said. “I think we need to anchor it in what the law was intended to do and not the way it has been abused today.”

McMahon said that the government wanted to close the loophole in the 1971 act, though legal advice was still needed on whether any change could apply retrospectively and allow Ahmed’s deportation. Officials are considering whether the law could be amended through the Immigration and Asylum Bill currently before Parliament.