Police guard Leytonstone station

A police officer stands guard outside Leytonstone station in north London yesterday, a day after three people were stabbed there. Photo: AFP, Mail Online
The attacker was filmed by a shocked bystander as he waved his knife (circled), before being Tasered by police. Photo: AFP, Mail Online
The attacker was filmed by a shocked bystander as he waved his knife before being Tasered by police. British counter-terror police were questioning the 29-year-old man on suspicion of attempted murder yesterday. Photo: AFP, Mail Online