Ruben Garcia from Annunciation House in El Paso told CBS News that 522 migrants were released Wednesday by U.S. Immigration and Customs Enforcement at sites in El Paso and Las Cruces, New Mexico. That raises the total number of people released this week to more than 1,000, after 186 people were released on Christmas Day and 400 were released in the two days before Christmas.

Another 500 could be released on Thursday. "It should be organized and orderly as it was today," Garcia said.

Local nonprofit groups told the CBS affiliate KBDC the key difference from earlier in the week was that they were notified in advance of the mass release by ICE — something the groups and U.S. Rep. Beto O'Rourke, who represents El Paso, said didn't happen previously.

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As a result, the nonprofits were more prepared for the large influx.

Day three of mass releases by ICE in #ElPaso. On this #Christmas day these three boys are enjoying some sweets. Their parents gave us permission to take their pictures. So far about 160 have been brought here. Waiting on another 40. pic.twitter.com/fAU1Lwo74n — Claudia Tristán (@ClaudiaKFOX_CBS) December 25, 2018

"They're coming from immigration cells so they're coming hungry, they're coming thirsty, most haven't bathed in a long time. The situation is really difficult for them," said Dylan Corbett, executive director of the Hope Border Institute.

ICE said in a statement earlier this week the mass releases were designed to ensure families weren't held longer than it's allowed to detain them, and blamed "decades of inaction by Congress" that resulted in the government being "severely constrained in its ability to detain and promptly remove families with no legal basis to remain in the U.S."

Many thanks to volunteers & donors who ensure that we take care of families being released by ICE in El Paso. 200 to be released today. Over 500 tomorrow. Please make a donation that will go to food and beds here: https://t.co/062olx7YIp pic.twitter.com/IPpFXCtiR8 — Beto O'Rourke (@BetoORourke) December 25, 2018

The immigrants released Tuesday by ICE were dropped off at a downtown El Paso bus station. Then, they were led by volunteers to a makeshift headquarters at Rock House Cafe and Gallery, a block away.

"This is what it is to give, this is what it is to receive people into your home and cherish time with other people," said Michael Patino, owner of the facility.

"We made something for (the migrants) for breakfast. We went to buy some bread and my sister went to her closet to look for things that we could give away. We are here to give what we have," Michelle Sanchez said.

Sanchez, an immigrant herself, told KDBC it was her duty to give back, saying, "If you can do something for the people, if you can give something for the people just do it. That's what we do and that's what we're trying to do here," Sanchez said.

One of the migrants said, "It's unreal, like a dream. They gave us clothes, food, everything. I really didn't expect this. Thank you so much."