The terror-related arrest of a teenager at Heathrow airport was not made in response to any immediate risk or threat, police said.
A 19-year old man has been arrested on suspicion of "preparing for acts of terrorism" in relation to Syria.
The man is currently held at a police station in London.
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Children's charity Kids Company is being investigated by the Metropolitan Police over criminal allegations.
A senior employee at a 4-star London hotel has been jailed for six years for raping a man who he lured to a fake job interview.
The Philae has now began delivering what is called the "ground truth" by touching and analysing the material on a comet's surface.