London: Owen Smith, the Labour lawmaker challenging Jeremy Corbyn for the leadership of Britain’s main opposition party, attacked his opponent for changing his story about overcrowding on a train he was travelling on.

Coverage of the incident, dubbed “Traingate” on social media, dominated domestic UK newspapers and broadcasters late on Tuesday and early Wednesday. It’s added an extra dimension to a Labour leadership contest, in which opponents of Corbyn have questioned his suitability as a potential prime minister. Most Labour lawmakers oppose Corbyn but he’s still favourite to retain the leadership in a vote among party members and supporters.

Earlier this month, Corbyn released a film he’d made sitting in a Virgin Trains corridor on a three-hour journey from London to Newcastle, saying he’d been forced to travel this way because there were no seats on the “ram-packed” train. He said the incident demonstrated that rail services should be taken over by the government. Virgin responded on Tuesday by releasing closed-circuit television footage from the journey that showed Corbyn walking past empty seats before he made the film, and then sitting down in one afterward.

While Corbyn’s campaign said that the empty seats had been reserved, or had bags on, and that the leader had wanted a seat with his wife, Smith said Corbyn had been exaggerating to make a “legitimate” point.

“Obviously, Jeremy did have a seat and he went to sit on the floor to make a point about overcrowding,” Smith told BBC Radio on Wednesday. “I’m not quite sure what the Corbyn version of events is. It changed a couple of times yesterday.”

Corbyn attempted to move on from the incident at an event in London Wednesday at which he was outlining his policy on the National Health Service, but he was pressed repeatedly on it by reporters at a news conference after his speech.

“We journeyed through the train looking for places, there wasn’t a place for us all to sit down, and so for 40 minutes or so I remained at the front of the train in the vestibule there sitting on the floor,” Corbyn said in response to the questioning. “It’s a really important issue this, absolutely crucial to the future of the whole country and the NHS.”