One person has now been released from hospital after being stabbed at the Wireless music festival in east London.
Two people were attacked during the event this weekend.
More top news
Large plumes of black smoke could be seen coming from the boat which caught fire while anchored on the River Thames.
London mayor Boris Johnson is under pressure to issue health warnings about his new double decker bus during the heatwave.
It's all over in a split second when you watch on TV. But just look at what happens when a serve at Wimbledon is played in super slo-mo.