Four people doing weed control work on a railway track in Japan were killed after being hit by an express train as it entered a station where they were working, officials said on Thursday.

The accident occurred at Shin-Kanuma Station, north of Tokyo, and involved the Tokyo-bound Spacia express train, the Tochigi prefectural police said.

The four, three workers and a supervisor, were rushed to a hospital but later pronounced dead, according to police and train operator Tobu Railway Co.

Six other people at the site, two other workers, three on lookout duty and an on-site supervisor, were safe, Tobu Railway said.

They had been assigned to spray herbicide. About 50 passengers on the train were also uninjured.