U.S. immigration authorities planned to release 500 migrants in El Paso by Wednesday evening, which would be the highest single-day figure in the city.

The release of migrants to shelters is common in El Paso, but advocates fear that the government may be dumping large numbers of immigrants on the streets to relieve overcrowding in the wake of the deaths of two children who were in Border Patrol custody.

Ruben Garcia, executive director of Annunciation House, an El Paso immigrant shelter that coordinates local assistance efforts for migrants, said immigrants would not be released to the streets on Wednesday, but instead will be placed directly into 11 temporary and permanent migrant shelters.

But earlier this week, ICE released hundreds of men, women and children at the Greyhound bus station in Downtown El Paso, leaving Garcia and others scrambling to find shelter for about 600 migrants beginning Sunday night and continuing through Christmas Day.

More:More migrants left by ICE in Downtown El Paso on Christmas; 2,000 expected by week's end

“I am really, really disappointed when my government does things like this," Garcia said of mass releases earlier this week. "The bottom line is you don’t release families with young children to the streets.”

CBP says works to relieve capacity problems in El Paso sector

On Christmas Eve, Felipe Gómez Alonzo, an 8-year-old boy from Guatemala, died after being held in custody with his father, Agustin Gomez, for six days.

Border Patrol agents apprehended the boy and his father in El Paso on Dec. 18. The two were transferred to the Alamogordo Station on Sunday because of overcrowding in El Paso.

In a statement issued late Tuesday night, CBP announced it will now perform secondary medical checks on all children in custody, primarily children younger than 10 years old. The statement also said that CBP is looking to relieve capacity issues in Border Patrol stations and checkpoints in the El Paso Sector, which includes El Paso County and New Mexico.

Garcia says immigration authorities may seek to release migrants more quickly after the deaths of two children in U.S. Border Patrol custody in the El Paso sector.

“I can’t speak for CBP. (But) because of the concern with a second child dying, it’s my opinion (that) to reduce the numbers in holding cells, I anticipate a large number of families being released to bring the number of people in holding cells to some kind of balance,” Garcia said.

Typically, ICE works with Garcia to see how much shelter-room is available in the El Paso area. ICE then transports the released migrants to the shelters.

“We work really well with ICE," Garcia said. “Communication had been going really, really well. They ask me what our capacity is and tell me what their numbers are. I think over this past weekend something changed.”

More:ICE drops off hundreds of migrants at Downtown El Paso bus station; shelters scramble

Migrants typically stay in El Paso only one or two days but shelters start filling up when there are delays in finding transportation to their destinations in other parts of the United States, Garcia explained.

“One of the things that made this different, the holiday situation made it difficult for families to find seats on the buses to depart El Paso,” Garcia said.

The temporary shelters are run with the help of hundreds of volunteers, church groups and donations, including the local restaurant industry that assists with meals.

There will be about 1,000 migrants in shelters in the El Paso-Las Cruces area with Wednesday’s arrivals, Garcia said.

Garcia said that he understands that U.S. Customs and Border Protection facilities may be facing overcrowding but dropping off families with children at a bus station at night isn’t the right thing to do.

“The solution can’t be ‘we will release them to the street’,” said Garcia, adding that CBP should work with nongovernmental groups and government officials to find solutions.

More:Guatemalan boy dies in US custody, CBP officials say; 2nd migrant child to die this month

Guatemalan man hit by car, killed in South El Paso highway accident

'Heartless expulsion'

The influx of migrants in the El Paso region is part of a wave of Central Americans seeking political asylum in the U.S. while fleeing poverty and violence in their homelands.

Bishop Mark Seitz said the El Paso Catholic Diocese is concerned about immigrants being left alone on El Paso's streets, at the bus station and at the airport.

"We understand that the facilities of Homeland Security are overcrowded, but the decision of our government to simply put these children and families — with no money, no tickets, no food, no access to phones — out on the street is inhumane and unconscionable," Seitz said in an email.

Seitz said the diocese is working with Annunciation House to house as many migrants as possible — about 300 to 400 a day, depending upon volunteer efforts and resources.

The diocese has sent messages to parishes asking for more volunteers and facilities.

"Our government has a responsibility when it takes these refugees into custody to provide for their basic needs. We do as much for death row inmates. With the recent deaths of two young children, the accounts of mistreatment in holding cells and the heartless expulsion of these families an undeniable picture is coming into focus and it is not one of which we Americans can be proud." Seitz said.

Seitz said that families fleeing Central America are trying to escape endemic violence and hunger. And the United States is responding by treating them badly, hoping others will not follow.

"The truth is they are running for their lives," Seitz said. "They will take whatever risks necessary. Meanwhile, we who are citizens of this most wealthy nation in the world are going to have to deal with the consequences of our hardened hearts. Clearly this Christmas the newborn Savior will find no room."

Situation worsens in Juárez and New Mexico, as well

In Juárez, Mexico, the Casa Migrante immigrant shelter was at its 475-person capacity on Christmas Eve on Monday and could no longer take in more people, the shelter announced. A temporary night shelter was set up Tuesday at a Juárez fire station, according to local news reports.

In Doña Ana County in New Mexico, two Catholic churches and a retreat center operate short-term shelters for migrants who are en route to other places across the United States, an effort the church calls Project Oak Tree.

But the facilities have had to temporarily shut down for two weeks around the holidays because so many volunteers are on vacation or otherwise not able to participate, said Leonel Briseño, coordinator for the project.

"We shut down this week and next week; we just don't have volunteers during the holidays," Briseño said.

A few non-Catholic churches also operate small migrant shelters in Las Cruces.

Daniel Borunda may be reached at 546-6102; dborunda@elpasotimes.com; @BorundaDaniel on Twitter. María Cortés González may be reached at 546-6150; mcortes@elpasotimes.com; @EPTMaria on Twitter.

More:More than 400 migrants cross border, surrender to Border Patrol in El Paso's Lower Valley