http://www.cnn.com/2015/12/05/europ...ml?sr=tw12515londontubestabbings603pStoryLink
Apparently, he was saying "this is for Syria".
(CNN)A man stabbed three people at an east London tube station Saturday before police subdued him with a stun gun and made an arrest, London's Metropolitan Police said.
Police said they were treating the stabbing at Leytonstone station as a terrorist incident.
One man sustained serious but non-life-threatening injuries, police said. Two others suffered minor injuries.
Apparently, he was saying "this is for Syria".