Two Austrian men have been charged after speeches by Nazi leader Adolf Hitler were reportedly played on a train's loudspeaker system.

"Heil Hitler" and "sieg heil" were among the phrases allegedly heard over the system on a train travelling between Bregenz and Vienna, Austrian news service APA reported.

An Austrian Green Party MP, who was on the train, tweeted "In the RailJet 661, several calls of "Sieg Heil" have just been broadcast through the loudspeaker system! The train attendant completely helpless.

"I hope there will be a report and clarification as soon as possible!"

He added in a reply to another Twitter user: "First completely senseless stuff, even funny stuff and suddenly a Hitler speech and shouts of salvation. It was pretty disturbing. The train attendant didn't know what to do anymore."

The suspects, who have not been named, were tracked down by police who looked at video from cameras on board the train.

Spreading Nazi propaganda in Austria is a criminal offence.

They are suspected to be behind two other similar incidents last week in the country, although it is unclear whether they involved Nazi slogans.

According to APA, the pair are thought to have opened the conductor's intercom cabins with a key owned by rail employees.