15 people, including a 3 year-old, detained by ICE in San Francisco, advocates say

SAN FRANCISCO (KGO) -- At least 15 people including four children with their mothers, were detained by immigration enforcement officers in San Francisco on Wednesday after attending what immigration experts describe as a regular "check-in" with ICE.

"ICE requires people who are going through the immigration court process or even people who have gone through the process and gotten relief to check in with them periodically," said Priya Patel, supervising attorney for California Collaborative for Immigrant Justice.

Priya Patel's client is a 25-year-old woman who attended her immigration meeting with her two children. She'd been asked to come in under special circumstances on Wednesday.

"They had been following all the conditions that ICE had put under them. My client was on an ankle monitor so her location was always known by ICE and again, she was complying. So, they were not expecting to be detained and suddenly they were," said Patel.

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Patel's client called her sister to alert the family of their detention.

"They were held overnight at an ICE office that is not designed to be a detention center. Our understanding is that they were in a cell overnight that doesn't even have beds, they were laying on the floor of this cell overnight and what we have heard via my client's sister is that they were not given food," said Patel.

San Francisco Mayor Daniel Lurie was asked about these detentions in a sanctuary city.

"We are gathering information, and we have been told by federal officials that they have alerted every county to any detainees. We haven't been alerted yet, so we are still gathering information," said Mayor Lurie.

ABC News confirmed ICE made 2,368 nationwide arrests on Wednesday. Numbers reflect orders from the White House to increase the detentions of undocumented immigrants. During a Congressional Hispanic Caucus meeting, state leaders highlighted the new strategies that are being used by ICE.

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"Showing up to court hearings and they are having their removal cases dismissed, you get that? Show up to court for your removal case and its dismissed. What do these individuals do? They walk out of the court room and immediately as they walk out of that court room, they are re-arrested and are put into what is called an expedited removal process," said California Congressman Lou Correa.

Legal experts are concerned this will lead to fewer undocumented immigrants showing up for their hearings, leading to even worse outcomes.

"This is an intentional fearmongering that is intended to terrorize our community," said Patel. "When we are talking about people who are complying and coming into ICE check-ins, ICE arresting them, stripping them from their communities, disappearing them, depriving them of food and the ability to sleep in a bed - of course it's going to have the effect of scaring people."

Patel's client along with her two children are being transported to a family detention center in Texas. As to the others, their attorneys are still trying to get answers.

We contacted ICE and have not heard back.