All 12 people arrested by officers investigating the London Bridge terror attack have been released without charge.

They had been picked up in Barking, east London on Sunday after a series of police raids.

Of the 12 people who were arrested, seven were women. A 55-year-old man was earlier released without charge.

Police have named two of the three men who carried out the attack, saying that Pakistan-born Khuram Butt, 27, of Barking, London, had been known to police and MI5 although there was no prior intelligence about an attack.

The other attacker was Rachid Redouane, 30, from Barking, who police said had claimed to be Moroccan-Libyan.

The attackers, who were shot dead by police, drove a hired van into pedestrians on London Bridge before stabbing people in the area around Borough Market.

Sources have told Sky News that police officers discovered what appeared to be molotov cocktails in the van. They said bottles were found that were filled with a colourless liquid and rags coming out of the top.

Meanwhile, the country's' top counter-terrorism officer has described the level of danger in the UK as being at a "completely different" level.

Mark Rowley, the Metropolitan police assistant commissioner said there needed to be a radical change in strategy to counter jihadi attacks.

"In nine weeks, we've had five plots foiled and three successful attacks. That is completely different to anything we have seen for a long time. As the prime minister has indicated, we're going to need to do some things differently.

"We're going to have to think again about the next iteration of our police and security service model, which has constantly had to innovate over many decades."

A vigil was held at Potters Field Park near London Bridge to remember the victims in which London mayor Sadiq Khan said the British capital would not be cowed by terrorism.

There are still 36 people in hospital, with 18 in a critical condition.