Venezuelan police guard a stretch of highway while a group of protesters stage an anti-government demonstration in Caracas, Venezuela, on Oct. 26. (EPA/MIGUEL GUTIEREZ) (Miguel Gutierez/EPA)

Venezuelan authorities stopped a Washington Post reporter at the Caracas airport late Monday night and denied him entry, in the latest case of blocking a foreign correspondent from covering the mounting political and economic turmoil in the South American country.

Immigration officials told Joshua Partlow, 38, a dual U.S.-Canadian national, that he lacked a required work visa. Partlow and many other foreign correspondents with non-U.S. passports had routinely visited Venezuela in the past without work visas.

Venezuela is mired in its worst recession in decades, and opposition groups have organized protests in recent weeks that have drawn hundreds of thousands of people. Another demonstration had been called for Thursday, although it was postponed late Tuesday.

Carlos Lauria, program director for the Americas at the New York-based Committee to Protect Journalists, said Venezuela adopted a regulation in 2004 requiring visiting correspondents to apply in advance for authorization from the Communications Ministry. But that has rarely been enforced in recent years.

“They are enforcing this selectively now, I think, because they don’t want coverage of the protests,” Lauria said in a telephone interview.

He said journalists from Spain, Peru and other countries have also been turned back at the Caracas airport in the past few weeks because they lacked authorization. The committee’s own representative was also denied entry to the country in late August, with officials saying he lacked press credentials from Venezuela.

American journalists have also been prevented from working in Venezuela. In August, the Miami Herald reported that its correspondent, Jim Wyss, was detained by Venezuelan immigration authorities on arrival at the Caracas airport even though he had a valid journalist visa. An ABC News correspondent, Matt Gutman, was picked up by security forces last week while reporting on poor conditions at a hospital and ordered to leave the country, according to news reports.

Partlow, based in Mexico City, had entered Venezuela three times over the past year using his Canadian passport to cover developments in the country. On Monday night, he was instructed to stay in the Caracas airport and board the next flight to Miami, which left Tuesday morning.

“This is a moment when the world should be watching Venezuela, and the barring of a Washington Post journalist at such a key juncture is both arbitrary and outrageous,” said The Post’s foreign editor, Douglas Jehl.

A spokesman at the Communications Ministry said Tuesday that he did not know the details of Partlow’s case. He said visiting correspondents were required to apply at least five days ahead of their trips for authorization from the ministry. Asked why officials had not previously enforced that requirement, he replied that “the ministry doesn’t have power over that” and said immigration authorities applied the law. He said he was not authorized to provide his name.

Another Post correspondent, Nick Miroff, a U.S. citizen, has tried repeatedly in the past year to get a visa to report from Venezuela but has not received a response from authorities. Venezuela’s government announced in February 2015 that it would require American visitors to get visas.

Lauria said that governments have the right to establish requirements for visiting journalists but that the committee was still waiting to see whether journalists would receive permission in a timely manner to report in Venezuela under its newly adopted practices.

Venezuelan President Nicolás Maduro’s popularity has shrunk amid an economic crisis that has caused widespread food shortages in the oil-rich country. The government is also under fire for marginalizing the political opposition, most recently by blocking a referendum to recall the president. The Vatican is coordinating talks between the government and opposition leaders in an effort to ease tensions.