ROME (AFP) -- A third man arrested for carrying out Saturday's deadly attack in central London is an Italian-Moroccan who was arrested last year on suspicion of trying to reach Syria, according to Italian media reports.

Italy's main media outlets said Youssef Zaghba, 22, was the son of an Italian mother from Bologna and a Moroccan father.

The couple were separated and their son, who had passports from both countries, lived mainly in Morocco with regular periods spent working in Britain.

The Italian reports said Zaghba was intercepted at the Bologna airport last year as he was about to board a plane for Turkey, apparently with the intention of joining Islamic State militants in Syria.

He was detained with only a small backpack, his passport and a one-way ticket to Istanbul.

Police reportedly found IS propoganda videos on his cellphone, but after an investigation, they failed to find sufficient evidence of links to terrorism to prosecute him.

As a result he was released, and being a holder of an Italian passport he was not liable for expulsion under the kind of administrative order Italy routinely uses against suspected Islamist militants from Morocco and Tunisia.

According to the reports, the British and Moroccan secret services were notified of Zaghba's status as a potential militant.

But British police said Zaghba was "not a police or MI5 subject of interest".

According to the reports, Zaghba was born in Fez, Morocco, and never lived for any extended period in Italy.

His mother told police last year that he had asked her for money to travel to Rome before he left on his abortive trip to Syria.