BUENOS AIRES, Argentina (AP) — Argentine officials are expressing concern over the large number of pregnant Russian women who have recently entered the country to give birth as a way to obtain an Argentine passport, claiming three Russian spies who were recently detained in Slovenia were citizens of the South American country.

Immigration authorities forbade six pregnant Russian women from entering Argentina this week — three on Wednesday and three on Thursday — saying they had falsely claimed to be tourists, Florencia Carignano, the national director for migration, told a local news channel.

At least some of the women have launched legal proceedings to be able to enter the country and a judge gave a green light to a habeas corpus petition Friday to allow the six women to provisionally enter Argentina.

“These women who didn’t commit a crime, who didn’t break any migratory law, are being illegally deprived of their freedom,” Christian Rubilar, who represents three of the six women detained at the Ezeiza International Airport outside Buenos Aires, said prior to the judge’s decision.

The pregnant women have put a spotlight on a phenomenon that has become evident in Argentina in recent weeks.

“The quantity really is very big each day, only last night in the last Ethiopian (Airlines) flight, 33 Russian citizens entered with pregnancies of approximately 32, 33, 34 weeks,” Carignano said.

In the last year, 21,757 Russian citizens have entered Argentina, including around 10,500 pregnant women and “the numbers have been increasing in the last few months,” Carignano said. “In the last three months, 5,819 women who were about to give birth entered” Argentina.

Anyone born on Argentine soil is immediately granted citizenship and having a national-born child accelerates the citizenship process for the parents.

The judiciary is currently investigating whether there is some sort of criminal organization bringing Russian women to Argentina. While authorities did not say why such a ring would bring pregnant women to Argentina, some speculate the country has the right mix of lax immigration laws with Russians not needing visas, free universal healthcare and a passport that allows access to many countries without a visa.

“They are ripping people off, taking advantage of the desperation of war,” Rubilar said.

Authorities emphasized officials do not have any issues with Russian citizens arriving in Argentina, but they want to make sure they really have plans to live in the country.

“We don’t have any problem with people from any nationality who want to come live in Argentina, who want to raise their kids here, invest in Argentina. The problem is that these people come, leave and don’t return to Argentina and they leave with a passport,” Carignano said.

Argentina is a country that has traditionally been open to immigrants, but red flags were raised in immigration offices after three Russian spies were detained in Slovenia with Argentine passports, Carignano said.

“These people surely came to have children in Argentina,” she said.

In late January, Slovenian media reported that authorities had detained two alleged Russian spies and this time the reports said one of the two held Argentine citizenship.

“If we don’t start to control who we give passports to what’s going to happen to us Argentines is that they’re going to start asking for visas everywhere and the passport will no longer have the trust that it has with other countries,” Carignano said, noting that Argentines can enter 171 countries without a visa.

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