The London mayor Sadiq Khan has urged the public to remain "calm and vigilant" as police investigate whether a knife attack that left one woman dead and five people injured was terror-related.
Please allow a moment for the live blog to load
Police were called just after 10.30pm to reports of a man armed with a knife assaulting people in Russel Square.
Armed units arrived at the scene around five minutes later and Tasered and detained the suspect.
Six people were injured during the incident, including the woman who died at the scene. Two other women and three men were hurt.
The suspect, a 19-year-old man, has been arrested on suspicion of murder and remains in custody.
A spokesperson for the Metropolitan Police said early indications suggested that mental health was a "significant factor" in the case, adding: "We retain an open mind regarding the motive and terrorism remains one line of inquiry."
The Homicide and Major Crime Command is investigating, supported by officers from the Counter Terrorism Command.
Assistant Commissioner Mark Rowley said: “This was a tragic incident resulting in the death of one woman and five others being injured. Early indications suggest that mental health was a factor in this horrific attack. However we are keeping an open mind regarding the motive and terrorism remains one line of inquiry being explored.
“As a precautionary measure, Londoners will wake up this morning to notice an increased presence on the streets of officers, including armed officers today. We would urge the public to remain calm, alert and vigilant.”
The Mayor of London, Sadiq Khan, said police were working to keep the capital safe and establish the "full facts".
“The safety of all Londoners is my number one priority and my heart goes out to the victims of the incident in Russell Square and their loved ones," he added.
“I urge all Londoners to remain calm and vigilant. Please report anything suspicious to the police. We all have a vital role to play as eyes and ears for our police and security services and in helping to ensure London is protected.
“Our police officers are doing an incredibly difficult job on our behalf and they have my full support.”
