Police detained "a number of people" after searching two addresses early Monday in the east London areas of Barking and Newham, as the investigation into this weekend's terror attack continued.
Counterterrorism officers searched the addresses around 4:15 am (0315 GMT), the Metropolitan Police said in a statement.
"A number of people have been detained and are at present being spoken to," the police said in a statement.
Residents said they heard loud bangs and gunshots early Monday.
Meanwhile, Christine Archibald has been named as the Canadian killed in Saturday night's attack. Archibald had "moved to Europe to be with her fiance," her family said.
"She had room in her heart for everyone and believed strongly that every person was to be valued and respected," a statement said, adding that Archibald "would have had no understanding of the callous cruelty that caused her death."
Seven people were killed and more than 48 injured late Saturday when three men drove a van into pedestrians on London Bridge before stabbing people at bars and restaurants in nearby Borough Market.
The Islamic State militia claimed responsibility late Sunday for the attack, as British Prime Minister Theresa May vowed an overhaul of the country's counterterrorism strategy.
Police said on Sunday that twelve people had been arrested in London so far in connection with the attack, and that one 55-year-old man had been released without charge.
