After temporarily suspending detentions and deportations for a year to allow migrants of Haitian descent to get their paperwork together to register for legal residency or citizenship, the Dominican Republic has resumed the controversial program.

On Friday, Bernardo Jimenez, director of the government's immigrant detention center, said six Haitians had been detained so far, but four were later released after proving that had applied for residency under the state's policy.

In 2013, a Dominican court ruled that children born to migrant non-citizen parents were ineligible for automatic citizenship. Following protests and criticism from the international community, Dominican officials passed a law allowing residents a pathway to naturalization, setting June 17 deadline for residency applications.

While nearly 289,000 people have enrolled in the immigration program, according to state estimates, more than 66,000 people are believed to have fled to Haiti to avoid questioning and threats of deportation.

Authorities said that only 25,000 people of Haitian descent have qualified to stay and work in the Dominican Republic after the deadline expired.

Many who returned to Haiti from the Dominican Republic had been living in for years or even decades in the Caribbean country, which shares a border with Haiti on the island of Hispaniola.

In Haiti, growing makeshift camps contain thousands of displaced people housed under sticks and bedsheets, and many live without access to basic sanitation or other needs.

Haiti's prime minister said on Thursday that the Dominican government program is causing a "humanitarian crisis."

The US State Department released a statement Friday calling on the Dominican government to "take measures adequate to prevent the risk of statelessness," and "to prevent the arbitrary deprivation of nationality for legal citizens."

"We recognize the prerogative of the Dominican Republic to remove individuals from its territory who are present without authorization," the statement read. "We urge the Dominican Republic to avoid mass deportations and to conduct any deportations in a transparent manner that fully respects the human rights of deportees."

Top photo shows__ people in the Dominican Republic waiting show a document issued to them by the Haitian embassy that details their place of birth.