Shortly before he and a friend gunned down 20 foreign tourists at Tunisia’s Bardo museum, Yassine al-Abidi sat down to breakfast with his family and left for work at his travel agency as usual. His relatives, mourning his death in a hail of police bullets, said they could not understand how a lively, popular young man with a taste for the latest imported clothes could have done such a thing.

They said he was typical of the young men of Tunis’ Omrane Superieur suburb. He graduated in French, held down a job and showed no sign of the hardline Islamist ideology that would drive him to commit the worst militant attack in a decade.

But relatives said last year he had begun to spend more and more time at a local mosque, following a pattern of radicalisation of Tunisian young men who then find themselves fighting in Syria, Iraq and Libya.

“I am sad for Yassine, but even sadder for the victims that Yassine killed. They were innocent, why did they have to pay the price of a false understanding of Islam,” said his uncle Mohamed Abidi. “They are the victims of terrorism. We are the victims of a demagogic network that wants only death.”

Four years after a popular revolt toppled autocrat Zine El-Abidine Ben Ali, Tunisia has had free elections but the new government is caught up in a low-level war with militants who have taken advantage of the new freedoms.

More than 3,000 Tunisians have left to fight in Syria and Iraq and the government estimates around 500 have since returned, fuelling fears of further attacks on Tunisia’s fragile new democratic state.

He started visiting a local mosque where ultra- conservatives gave talks on jihad

Abidi and his fellow gunman were trained at a jihadist camp in Libya before the Bardo attack, the Tunisian government has said. Officials said the two men had been recruited at mosques in Tunisia and travelled to Libya in September.

Family members said Abidi had left home for two months, saying he would be working in the commercial city Sfax on Tunisia’s coast. But he did not display any of the conservative beliefs of hardline Islamists, never, for instance, complaining about alcohol being consumed at his uncle’s house.

“He was always fun, we danced together at family weddings. He wasn’t like hardline Salafists,” said his cousin Hanen.

“On the last day he had breakfast of dates and olive oil and went to work. At 10am he asked for a break and went and did what he did.”