India's state-run railway has suspended seven workers after brakes failed on a 22-coach train carrying hundreds of passengers, letting it run freely in reverse for about 13 km, officials said on Monday.

The train, en route from Ahmedabad in the western Indian state of Gujarat to Puri in Odisha state in the east, rolled downhill for about 45 minutes on Saturday before gradually slowing to a halt, the latest in a series of accidents involving the world's fourth-largest rail network.

It was not immediately clear what speed the runaway train reached but no casualties or injuries were reported.

Iron tools used to stop trains were not properly put in place, according to a senior railways official.

"By the time the train had rolled down to the nearest station, it had slowed down drastically and it was brought to a halt with the help of wooden wedges," the official said, adding that passengers also helped stop the train.

Indian Railways employs 1.3 million people and is filling tens of thousands of vacant positions for engine drivers, technicians, carpenters, track inspection crews and other roles related to improving safety in the world's fourth-largest network.

Investigations were under way.

Sign up to our free newsletters

Get the best updates straight to your inbox:
Please select at least one mailing list.

You can unsubscribe at any time by clicking the link in the footer of our emails. We use Mailchimp as our marketing platform. By subscribing, you acknowledge that your information will be transferred to Mailchimp for processing.