A 16-year-old American girl is missing in the UK after flying from New York to London after reportedly texting an older man.
British and American police are attempting to locate Victoria Grabowski after she flew to the UK at the weekend.
Metropolitan Police officers have spoken to Victoria's family and are treating the case as a missing persons investigation.
The force said: "The Met was contacted by the National Crime Agency regarding a 16-year-old US citizen who is believed to have travelled to the UK via Heathrow Airport on Saturday, August 24.
"She is being treated as a missing person and inquiries to find her are ongoing.
"Officers have liaised with her family and will be speaking with the New York Police Department."
New York police said Miss Grabowski, from Queens, boarded a flight from John F Kennedy Airport on Saturday and arrived in the UK on Monday morning.
US media reports say her parents discovered texts showing she had been communicating with an older man in Britain.
She had also paid for her ticket in cash, though her parents did not know how she acquired the money.
"She left JFK on Saturday morning and reached the UK on Monday morning," a New York Police Department spokesman said.
"We're working in conjunction with UK police, but unless she contacts us, we're not going to know too much more."
US reports said Victoria is a Polish citizen and used her Polish passport to board the flight.