Counter-terrorism officers have arrested an 18-year-old woman on suspicion of terrorism at a London airport, police said Friday. 

Authorities arrested the woman Friday afternoon at Stansted Airport on suspicion of plotting terrorist acts, according to London's Metropolitan Police Department. She was arrested upon landing at the airport, officials said. It was unclear where her flight had originated.

The woman, who has not been identified, was taken to a central London police station where she remains in custody.

Sources told Sky News the arrest was part of an earlier investigation that led to the Oct. 29, 2014 arrest of a 21-year-old man in Hackney on suspicion of assisting anothers to commit acts of terror, but it was not clear what his relationship might be to the woman.

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