A number of "staggering" Conservative losses have been blamed on the long-running dispute on Southern Railway over staffing and the role of conductors.

Hundreds of thousands of passengers have suffered over a year of travel misery because of strikes and other problems such as staff shortages.

The Conservatives lost seats in Croydon, Eastbourne and Brighton, while a number of others have become marginals, including Hastings where Home Secretary Amber Rudd came close to defeat.

Mick Cash, general secretary of the Rail, Maritime and Transport union, said: "These results prove that the toxic Southern Rail franchise was a game changer in key seats along the routes served.

"RMT is demanding that the axing of the guards is reversed and the union will harass Theresa May and the transport ministers in her minority government every step of the way as we step up the fight to put safety and access to services before private profit and greed."

Emily Yates, co-founder of the Association of British Commuters, said: "Once again, we see the public in the south reject the narrative that Southern Rail and the Government have been pushing over a whole year of commuter suffering."

She said passengers knew before the election that the Department for Transport was holding back a report by Chris Gibb analysing the causes of the Southern Rail crisis, for nearly six months.

"The Gibb report has been said to be highly critical of the DfT's role in this affair, and its ongoing suppression is insult upon injury for commuters in the south.

"With this staggering result we hope that MPs of every political colour will finally stand up and join our call for its immediate release," she said.

The report looking into Southern owner Govia Thameslink Railway, was carried out by Chris Gibb, a non-executive Network Rail director with 35 years' experience in the industry.

The Department for Transport received the report at the end of last year and has faced increasing calls to publish its contents, but refused.