 -- Police have identified the third man involved in the attack on London Bridge and Borough Market Saturday night that killed seven people and injured more than 40 others.

The Metropolitan Police announced today it believed 22-year-old Youssef Zaghba of East London is the last of the attackers named, all of whom were shot dead by police.

The identities of the other suspects, Khuram Shazad Butt, 27, and Rachid Redouane, 30, also of East London, were announced Monday.

Transport for London (TFL) confirmed today that Butt worked for London Underground after an image surfaced that allegedly showed his working at the West Kensington subway station.

“Khuram Butt worked for London Underground for just under six months as a trainee customer services assistant, leaving in October last year," the TFL said in a statement.

Butt was also featured in a 2016 documentary on the British Channel 4 called “The Jihadist Next Door,” ABC News reported Monday.

All three attackers were confronted and shot dead by armed officers within eight minutes of being called, police noted.

Police arrested a 27-year-old man in connection with the attack and released 12 others without charges, officials said today.

Authorities are now trying to "piece together exactly what occurred" and learn more about the attackers, Metropolitan Assistant Commissioner Mark Rowley said Sunday.

"Work is ongoing to understand more about them, their connections and whether they were assisted or supported by anyone else," Rowley said. “[W]e will release the identities of the three men directly responsible for the attacks yesterday, Saturday, 3 June, as soon as operationally possible.”

Saturday’s deadly attack marked Britain’s third such incident since March.

It comes in the wake of a suicide bombing outside an Ariana Grande concert in Manchester on May 22 that killed 22. A separate vehicle ramming attack in March on Westminster Bridge left four dead including the suspect.