A Commons committee has heard that Mohammed Ahmed Mohamed, who escaped from a mosque in West London, was involved in fighting, attack planning and recruiting for Al Shabab in Somalia.
The Home Affairs Committee is hearing evidence from David Anderson, the independent reviewer of terror laws. Anderson says Terrorism Prevention and Investigation Measures are not a foolproof way of keeping the population safe, adding:
"I'm troubled by the fact that there are cases which can't be prosecuted at all."
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Tributes have been left in Caledonian Road in Islington where 15-year-old Alan Cartwright died after he was stabbed.
A boy has died after he and his friends were attacked while cycling in north London.
Three police officers have been praised for their actions in helping a four-year-old boy who had become stuck on a roof in Newham.