Police investigating the terror attack at London Bridge, in which eight people died, have made another arrest.
The report said Italy had put him on a watch list and flagged his presence to Moroccan and British authorities.
On Monday the Metropolitan police's counter-terrorism command said it knew the identity of all three attackers, but: "Inquiries are ongoing to confirm the identity of their accomplice". Redouane, who also used the name Rachid Elkhdar with a different birth date putting his age at 26, had claimed to be Moroccan and Libyan, police said.
The Metropolitan Police said a 27-year-old man had been arrested in Barking on Tuesday in connection with the investigation.
As the British nation stood still in a sign of respect to the victims of the latest terrorist attack in London on Tuesday, security issues are now the focus of United Kingdom election campaigning with only two days remaining before the June 8 snap poll.
The body was found late Tuesday about two kilometres (over one mile) downstream from London Bridge, where Saturday's van and knife attacks began.
All three perpetrators were confronted and shot dead by armed officers within eight minutes of the first emergency call.
Scotland Yard has confirmed that Butt was known to police and MI5 but said there was "no intelligence to suggest that this attack was being planned" and the probe "had been prioritised accordingly".
The so-called Islamic State (IS) group has said its "fighters" carried out the attack.
Italian authorities tipped off Britain about his movements. According to the reports, Zaghba was born in Fez, Morocco, in January 1995.
The revelations add to concerns that security services repeatedly missed opportunities to stifle the threat from Butt.
One of those attackers, Khuram Shazad Butt, was a known extremist and had even appeared in Channel 4 documentary "The Jihadis Next Door".
At the time of the attack, Zaghba was working in a London restaurant and continued to have contacts with his mother in Italy, where he visited in 2016, the Italian newspaper Corriere della Sera reported.