BUDAPEST, Hungary — Hungary’s largest left-wing political newspaper suspended publication because of “considerable” losses, its owner said Saturday. The move was condemned by opposition parties across the political spectrum, who accused Prime Minister Viktor Orban’s government of trying to extend its dominance over the media.

In the capital of Budapest, thousands of people attended a rally Saturday afternoon to support freedom of the press and the Nepszabadsag paper outside parliament. Some lit a bonfire using copies of a pro-government newspaper.

Mediaworks said it was searching for the “best business model” for the Nepszabadsag paper, offering subscribers alternative publications or refunds. The company did not say when the newspaper might reappear but said it wants to “preserve Nepszabadsag for the future.”

Mediaworks said the paper lost more 5 billion forints ($18.4 million) since 2007 and was generating “a considerable net loss” so far this year.

Journalists at the newspaper said they weren’t given advance notice and described the suspension of the paper’s print and online editions as a “coup.”

“The Nepszabadsag newsroom found out at the same time as the public that the newspaper had been shut down effective immediately,” journalists wrote on the paper’s Facebook page. “Our first thought is that it’s a coup. We’ll be in touch soon.”

Many questioned the timing of the suspension. In the past few days, the paper had broken several stories highlighting suspicions of government corruption — including reporting on the extravagant travel arrangements of a senior minister and a personal scandal involving the president of the National Bank of Hungary.

“The total undermining of Nepszabadsag is the latest example of Viktor’s Orban’s megalomania,” said Adam Mirkoczi, spokesman of the far-right Jobbik party. “The only aim of Fidesz is to either gain 100 percent control over Hungarian media or to obstruct it.”

“I have a lot of respect for my colleagues who wrote the investigative journalism stories, these very strong articles,” said Zoltan Trencsenyi, a journalist at the suspended paper who attended the rally.

Hungary’s media landscape has changed considerably in the last few years, with many print and online publications as well as radio and television stations coming under the control of Orban’s inner circle and then taking on a noticeable pro-government bent.

“My modest opinion is that it’s high time for Nepszabadsag to unexpectedly shut down,” said Szilard Nemeth, vice chairman of Orban’s governing Fidesz party, alluding to the newspaper’s communist-era roots.

There had been considerable speculation that Nepszabadsag and other Mediaworks publications will be sold to one of Orban’s allies. Ad expenditures from government and state-owned enterprises, an important revenue source for media, have notably favored publications toeing the government line.

Mediaworks, owned by Austrian private equity firm Vienna Capital Partners, controls a large sector of the Hungarian print media market, including the Vilaggazdasag business daily and the Nemzeti Sport sports daily. Last year, it acquired the 27.7 percent stake in Nepszabadsag that had been owned by a foundation set up by the Socialist Party, the country’s largest leftist opposition group. Last week, the company announced the acquisition of regional newspapers in 12 counties.

The leftist Together party said Orban moved to get the paper suspended because investigative journalism stood in his way.

“With this action, the Orban regime’s battle against freedom of the press has reached its peak,” said Together chairman Viktor Szigetvari.

Nepszabadsag, launched in 1956 and under the control of Hungary’s ruling communist party until 1989, has a circulation of around 40,000, down from around 115,000 in 2008 and 270,000 in 1995.

Andras Nagy contributed to this report.