Six People Stabbed in a Knife Attack in London's Russell Square

A woman has been killed, and five others injured, during a knife attack in the London borough of Camden. Metropolitan Police were called to Russell Square around 10:30 PM Wednesday evening (London time) after reports of a young man wielding a knife and stabbing people. Within five minutes, officers arrived at the scene and tasered a 19-year-old before arresting him. He's currently being held under police custody in hospital.

"Early indications suggest mental health is a significant factor in this case and that is one major line of inquiry," police said in a statement. "But of course at this stage we should keep an open mind regarding motive and consequently terrorism as a motivation remains but one line of inquiry for us to explore."

Metropolitan Police confirmed its homicide unit will be working with the counterterrorism unit on the investigation. The Guardian is reporting that "Scotland Yard's counter terrorism command, known as SO15, are involved in the investigation" as well.

It has been revealed that the woman who died was in her 60s. There is no confirmed information about the other victims at this time, other than that they included four men and one woman.

Police cordon around — Helen Edwards (@hyperlinkhelen)August 4, 2016

REPORT: Сounter terrorism unit joins investigation into — Mike Hall (@The_News_center)August 4, 2016

Police have cordoned off Russell Square, and were redirecting traffic away from the park overnight. Officers told reporters that there will be an increased police presence in London on Thursday, including armed officers, "as a precautionary measure."

This may include Metro police's new anti-terror unit, revealed just hours before the attack. The unit's 600 officers will patrol armed, unlike most London police who do not carry guns.

More as this story develops.