Immigration and Customs Enforcement (ICE) officials are raiding targets in "sanctuary cities" to pressure those jurisdictions to cooperate with federal immigration agents, CNN reported Friday, citing a senior U.S. immigration official familiar with the situation.

A sanctuary city is any territorial area in which the local law enforcement bodies don’t coordinate with federal authorities to deport illegal immigrants. Several areas such as San Francisco, California, Connecticut, New Mexico, Colorado, Connecticut, Rhode Island, North Dakota and Oregon have been identified as sanctuary cities. 

CNN's source reportedly revealed that senior ICE officials have discussed carrying out more operations in these areas during internal meetings.

"There's been questions about whether Austin is being targeted. We had a briefing.... that we could expect a big operation, agents coming in from out of town. There was going to be a specific operation, and it was at least related to us in that meeting that it was a result of the sheriff's new policy that this was going to happen," U.S. Magistrate Judge Andrew Austin said during an immigration hearing Monday, adding that an Austin raid in mid-February was done to retaliate to a local sheriff's limited cooperation with ICE

However, ICE  has categorically denied any suggestion that the operations were specifically aimed at the sheriff's county.

Read: Sanctuary Cities 2017 Map: List Of Places Protecting Undocumented Immigrants

"Rumors and reports that recent ICE operations are specifically targeting Travis County, Texas, apart from normal operations, are inaccurate," read a response from ICE, which continues on to say "more ICE operational activity is required to conduct at-large arrests in any law enforcement jurisdiction that fails to honor ICE immigration detainers."

The case in Travis County, Austin pertains to Sheriff Sally Hernandez's adoption of a sanctuary policy in the county, which was announced in the beginning of February. Her department announced that it would not be obliged to detain suspected undocumented immigrants in local jails for 48 hours pending immigration review from federal agents. Only exceptions being individuals arrested for murder, sexual assault or human trafficking, or against whom a warrant had been issued.

But just days following the adoption of the new measures, a series of raids were made, during which 51 people were arrested.

"My understanding, what was told to us, is that one of the reasons that [the raid] happened was because the meetings that had occurred between the (ICE) field office director and the sheriff didn't go very well," Judge Austin said during the hearing.