Two dozen immigrants detained in Louisiana are on a hunger strike to protest being locked up as many seek asylum in the United States.

Immigrant advocates say the strike started last week with about 150 people, but U.S. Immigration and Customs Enforcement says only 24 people have continuously denied meals.

Immigrants and their advocates routinely complain about poor conditions and medical care in detention, but those at River Correctional Center in Ferriday, about 100 miles north of Baton Rouge, say they are frustrated with the poor attention to their cases and being denied bond.

ICE began contracting with the privately run prison on a temporary basis this year to deal with a spike in immigrants coming through the U.S.-Mexico border. About 500 people are held there, spokesman Bryan Cox said.

Those on strike say they have limited access to ICE staff and haven't been able to convince a judge that they should go free while their asylum cases wind through immigration court.

"It's a charade of due process," said Rachel Taber, an organizer with the New Orleans Workers' Center for Racial Justice who met with the immigrants this week.

"Their perception is that this will not be a real justice or a real court process," she said.

The Executive Office for Immigration Review, which oversees immigration courts, said it didn't have statistics readily available to show how many people have been granted bond in the court where the detainees appear.

ICE, which defines a hunger strike as someone rejecting nine consecutive meals, says it respects the rights of people to voice their opinion without interference.

"ICE does not retaliate in any way against hunger strikers," Cox said, adding that the agency explains the negative health effects of not eating and closely monitors those who avoid meals.

The strike follows one in El Paso in which ICE force-fed some of the detainees after obtaining a court order.

Immigration authorities are facing a surge in people crossing the southern border, particularly Central American families and children who are fleeing extreme violence and poverty. Many are seeking asylum.

President Donald Trump threatened Friday to shut down the border unless Mexico immediately stops illegal immigration.