"Eleven people have been arrested following three murders across London this weekend and detectives investigating a fatal stabbing in Wandsworth have charged two people," the Met Police said.
Two young men were killed within minutes of each other in Wandsworth and Greenwich on Friday, according to London Mayor Sadiq Khan, who said he was "sickened" by the news.
A man in his 30s was stabbed to death in Tower Hamlets on Saturday. Media reported two other stabbings near Clapham North metro station, saying the attacks were not related.
Deputy Assistant Commissioner Matthew Twist said police were following more leads and stepping up visible presence across London this weekend.
Khan tweeted assurances that there was "no higher priority for me than Londoners’ safety." US President Donald Trump likewise took to Twitter this week to accuse him of being a "disaster" and suggest the city needed a better mayor.