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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Cloud and rain first thing but it will gradually dry up from the north west. Becoming bright in the west, staying quite cloudy in the east
Rain becoming more persistent overnight. Rain and cloud slow to clear tomorrow but becoming dry by the afternoon. Some brightness later