Seifeddine Rezgui – the student who carried out the murderous attack in the Tunisian resort of Sousse which left at least 30 Britons feared dead – disappeared along with six other young men he shared a house with a month before the slaughter on the beach, The Independent understands.

A number of the men, who had rented the property next to the Mosque of the Seven Virgins in the Islamic holy city of Kairouan, remained at large.

The group led secretive lives, deliberately avoiding contact with local people, according to neighbours, who also claimed that there were visits by a group of Salafists before the building was suddenly left empty. Authorities in Tunisia are “sure” Rezgui had help in Friday’s murderous rampage – though not direct – and are searching for his accomplices.

There were reports that the 23-year-old Rezgui had recently visited his home town of Gaafour, 50 miles south-west of Tunis. The identities and whereabouts of his housemates remain unknown. A Tunisian official involved in the inquiry said the authorities were trying to trace the men because they may have vital information about their dead housemate.

Isis, which had given Rezgui the name of “Abu Yahya al-Qayrawani” [from Kairouan], has claimed responsibility for the shooting of the 39 tourists in Sousse, along with the bombing of a mosque in Kuwait and a decapitation in France on the same day.

Rezgui, however, was not on any security watchlist in Tunisia. In London, the Home Secretary, Theresa May, presided on Sunday morning over a meeting of the emergency committee Cobra, saying authorities do not believe Rezgui was singling out British tourists, but was randomly killing anyone who looked European.

The government in Tunis has announced that it will put in an extra 1,000 armed police to protect tourist facilities and hotels after hundreds more were deployed at beach resorts in the aftermath of the massacre. The state news agency, TAP, reported that gunmen had raided homes for food in el Kef, around a 100 miles from the coast, before heading into hills bordering Algeria. It was unclear whether there was connection between this and the Sousse killings.

Seifeddine Rezgui was given the name of “Abu Yahya al-Qayrawani” by Isis, who have subsequently claimed responsibility for the attack (AP)

The Foreign Office in London stated that further attacks may follow in Tunisia. The warning was echoed by the Imam of the Great Mosque of Sidi-Uqba in Kairouan who maintained that it was “inconceivable” that Rezgui was not prepared for the murders by others. He added that the jihadist group Ansar al-Sharia, an al-Qaeda affiliate banned in Tunisia, was among the chief suspects although, he said, there may also be an Isis connection.

Imam Taib al-Gazi told The Independent that “damaging actions by weak governments” which followed the overthrow of the dictator Zine el Abidine Ben Ali four years ago had contributed to Kairouan being infected by extremism.

“From 2011 to last year we had all kinds of imams coming here, from Tunisia and abroad, from Saudi Arabia and Gulf States and other places to spread this kind of thought. This has now been stopped by the new government, but there were plenty of opportunities for this man Rezgui to be indoctrinated,” said Imam Taib.

However, the imam said he was against an emergency measure announced by the Tunisian Prime Minister, Habib Essid, to shut down 80 mosques accused of espousing violence. “It would be better to change the imams there. None of these mosques is in Kairouan. We had trouble like that in two mosques last year and we changed the imams”, he said.

Imam Taib al-Gazi said foreign imams had been coming to Tunisia and preaching extremism

The imam said he acknowledged that extremists wanted to use houses of worship to spread their “bad message”. Ansar al-Sharia was allowed by the government of the time to hold a meeting at the Great Mosque two years ago. “It was a big mistake; we were against it – we did not give our permission for this,” he stressed.

“Also the people of Kairouan were against it. They had to put the police in front of the mosque to protect Ansar from the angry people of this city. The following year Ansar tried to use the mosque again, this time they were stopped from even entering Kairouan.

“What happened shows that Kairouan is not place for terrorists. Because this killer lived here for a while, this city is now getting a bad name. But he wasn’t even born here.”

Many others in Kairouan, 60 miles away from Sousse, also felt that the presence of Rezgui had unfairly tarnished the image of the city.

The residents of Sidi Belkacem district complained that they faced being traduced because the murderer had lived among them.

“But it was only for about eight months and we hardly ever saw them during that time. They went to that mosque but never mixed,” 22-year-old Imene Mohammed wanted to explain. “Whenever they were going to and from the house they would just look at the ground. This was not just with women – they would not look at the men either.”

Youssef Echarfi nodded his head: “They would do anything not to talk to you; they would not even talk to you at the mosque. They were not rude but would pretend to be on the phone so as not to have a conversation.

“Towards the end they just kept themselves shut up in the house. Now I wonder what was going on in there. Then they had visitors, men with big beards and again I wonder what was going on.”

Policemen patrolling the beach in front of the Riu Imperial Marhaba Hotel in Sousse where tributes have been laid to the dead (AFP/Getty)

It is not, of course, known whether Rezgui’s journey to becoming a killer began at his birthplace. His Facebook postings had begun to change from expressing his fondness of techno music and breakdancing to jihad and death. His last entry on New Year’s Day 2015, when he was living in the Belkacem district, read: “May God take me out of this unjust world and perish its people and make them suffer. They just remember you when you die.”

Rezgui’s murderous rampage has had a profound impact on Tunisia’s main source of income and employment, tourism. Three thousand foreign visitors left in 24 hours after the killings.

The government will be holding meetings with foreign ambassadors to describe the new security measures being taken to protect their nationals.