London attack: Three arrested in east London

Khuram Butt, Rachid Redouane and Youssef Zaghba have been named as the London Bridge attackers

Police investigating the London terror attack have made three fresh arrests, following raids involving armed officers in east London.

Two men were arrested on suspicion of terrorism offences and a third man was arrested on suspicion of drug offences. Seventeen people have now been arrested in connection with Saturday's attack and five remain in custody.

Clockwise: Chrissy Archibald, Sebastien Belanger, Kirsty Boden, Ignacio Echeverria, Sara Zelenak, Xavier Thomas, Alexandre Pigeard and James McMullan were all killed in the attack

Eight people were killed when three men drove into pedestrians on London Bridge before stabbing people. All of those who died in the attack, which began at 21:58 BST on Saturday, have now been named.

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The latest arrests were made as counter-terrorism officers carried out two search warrants in east London on Wednesday night.

Two men were arrested on a street in Ilford, the Metropolitan Police said. One of the men, aged 27, was held on suspicion of the preparation of terrorist acts, while a 33-year-old man was arrested on suspicion of possession with intent to supply controlled drugs.

A third man, aged 29, was arrested on suspicion of the preparation of terrorist acts at an address in Ilford. She said her son was under surveillance when he was in Italy and questioned why this was not the case in the UK.

An Italian police source confirmed to the BBC that Zaghba had been placed on a watch list, which is shared with many countries, including the UK.

In March 2016, Italian officers stopped Zaghba at Bologna airport and found IS-related materials on his mobile phone. He was then stopped from continuing his journey to Istanbul.

The BBC understands he was not prosecuted but was listed on the Schengen Information System, an EU-wide database which includes details of potential suspects.

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When Zaghba entered Britain, staff at passport control should automatically have been alerted by the Schengen system, BBC home affairs correspondent Danny Shaw said.

"One unconfirmed report suggests that did happen, apparently when Zaghba arrived at Stansted Airport in January - but that border staff still let him in," he said.

It earlier emerged that Khuram Butt was known known to police and MI5 in 2015, but the Metropolitan Police said there had been no evidence of a plot. Butt had appeared in a Channel 4 documentary The Jihadis Next Door, broadcast last year.

The married father-of-two, who worked for London Underground, could be seen in the programme arguing with police officers in the street, after displaying a flag used by so-called Islamic State in a London park.

Two people in Barking, east London, had also raised concerns about Butt and had called a hotline to warn about him.