BREAKING NEWS: At least 30 injured as train derails platform and rides UP escalator at Chicago O'Hare airport

At least 30 people have been injured after a train flew off the tracks and up an escalator at Chicago O'Hare Airport this morning.

The Blue Line vehicle ploughed through the end of the platform towards the entrance of the terminals shortly before 3am.

Passengers were taken to three hospitals in the area to be treated for minor injuries.

Chicago Fire Commissioner Jose Santiago told a press conference at O’Hare the train operator 'was walking and talking as we were investigating,' according to the Chicago Tribune.

An anonymous Transportation Security Administration employee told NBC Chicago: 'I thought it was just a hard stop as the train didn't even slow down when it was coming in. It was chaos.'

Chicago Transit Authority spokeswoman Lambrini Lukidis said a bus rail replacement service has been set up for passengers as trains are suspended in the surrounding area.

Located in north-west Chicago, O'Hare International is the world's fifth busiest airport after Beijing, Heathrow, Atlanta, and Tokyo Haneda.

Around 66million passengers pass through a year flying to more than 60 foreign destinations.
The underground station for Blue Line subway trains opened in 1984.

It is open 24 hours a day, seven days a week.

The O'Hare branch, the longest section of the Blue Line, uses the firm's oldest vehicles, as well as some of the newest.