A man and a woman have been detained by specialist officers at Heathrow Airport on the suspicion of "the commission, preparation or instigation of acts of terrorism".
It's understood that the couple were arrested after arriving on a flight into the airport.
Police are searching two separate addresses in East London as part of their inquiry.
"The arrests form part of an investigation into travel to Syria in support of alleged terrorist activity."
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Dry with clear spells overnight. Dry and breezy with sunny spells for much of tomorrow. Rain arriving later. Becoming humid from Monday.
Showers fading away with clear spells overnight. Dry with sunny spells for much of tomorrow with rain arriving later. Becoming humid later.
Feeling warm in this afternoon's sunshine. Breezy at times with the risk of an isolated shower.