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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A headteacher has payed tribute to a seven-year-old boy who was killed in a bus crash in Coventry at the weekend.
The daughter of a woman killed when a double-decker bus crashed into a Sainsbury's has told ITV News she will be "sadly missed by all".
A group of disabled activists threw toys and balls at him as he entered the conference.