One of the attackers who carried out the Easter Sunday bombings in Sri Lanka studied aerospace engineering at a British university and lived in London while a student.

UK counter-terrorism investigators believe Abdul Lathief Jameel Mohamed attended Kingston University in south-west London from 2006-07.

British investigators were searching for any associates or signs of extremist activity during his time in the UK.

Mohamed later went on to study in Australia and on Sunday took part in a wave of suicide bombings at churches and hotels in Sri Lanka that killed at least 359 people and injured more than 500. Islamic State has claimed responsibility for the bombings, believed to be the most lethal conducted by the group.

Mohamed’s identity came to light after Sri Lanka’s defence minister, Ruwan Wijewardene, told a media briefing earlier on Wednesday that one of the bombers had studied in the UK and done postgraduate studies in Australia before returning to settle in Sri Lanka.

Wijewardene said there were nine suicide bombers in total – mostly well educated and from well-to-do families. Eight had been identified and one of them was a woman, he said.

“This group of suicide bombers, most of them are well educated and come from middle or upper-middle class, so they are financially quite independent and their families are quite stable financially,” Wijewardene said “That is a worrying factor in this. Some of them have I think studied in various other countries, they hold degrees, LLMs [law degrees], they’re quite well educated people.”

Two of the bombers were brothers, sons of a wealthy spice trader and pillar of the business community, a source close to the family told Reuters. Inshaf Ibrahim, a 33-year-old copper factory owner, detonated his explosive device at the busy breakfast buffet of the luxury Shangri-La hotel, the source said.

A picture purporting to show Inshaf Ibrahim that emerged on Wednesday.

When police went later that day to raid the family home, his younger brother Ilham Ibrahim detonated a bomb that killed him, his wife and the couple’s three children, the source told Reuters.

However, there appeared to be confusion over Ilham Ibrahim’s role, with other media reports naming him as the bomber of the Cinnamon Grand Hotel and identifying his wife as the female bomber who detonated the explosives when police arrived at the family home.

Sri Lankan authorities have not released the identities of any of the bombers, and police did not respond to a request for comment.

Ilham Ibrahim, 31, openly expressed extremist ideologies and had been involved in meetings of National Thowheed Jamath, a local Islamist group suspected of involvement in planning the attacks, according to the Reuters source.

His entrepreneur brother, Inshaf, was outwardly more moderate in his views, and was known to be generous with donations to his staff and struggling local households, the source said. Inshaf was married to a daughter of a wealthy jewellery manufacturer and he faced no problems with money.

British counter-terrorism investigators said they were unaware Sri Lanka was going to announce that one of the suspected attackers had British links. A Metropolitan police spokesperson said: “We do not discuss who we may or may not be investigating as part of counter-terrorism investigations.”

The spokesperson added: “Whilst there is currently no intelligence to suggest there is any threat to the UK in relation to the attacks in Sri Lanka, we continually work closely with our security partners both here in the UK and internationally in order to keep the public safe.”

More than 60 people have been arrested so far as part of investigations into the plot.

Despite the scale of the security operation, Sri Lanka’s prime minister, Ranil Wickremesinghe, warned that several suspects armed with explosives had yet to be found.

Wickremesinghe said there were more explosives and militants “out there”, and confirmed reports there had been a failed attack against a fourth major hotel, and that the Indian embassy was also a possible target.

Additional reporting by Michael Safi in Colombo