COMMUTERS had to leave a train this morning (Wednesday) after smoke was spotted as it travelled through Brookmans Park.

At around 8.20am Hatfield fire crews were called to the scene.

Crew commander Mark Pidduck said: “It was an overheated transformer on a southbound slow train.”

A First Capital Connect spokesman said: “Passengers were taken off the train at Hornsey and the train is being investigated.

“It is difficult to know at this stage what it was.”