U.S. Citizenship and Immigration Services (USCIS) said this week it has ended a policy that allows migrants to not be deported while they or their family members receive life-saving medical treatments.

A USCIS spokesperson told The Hill in a statement Tuesday that the change took effect Aug. 7 but provides exemptions for military families.

The spokesperson added that the policy is not ending, but will instead be handled through Immigration and Customs Enforcement (ICE).

"As with any request for deferred action, ICE reviews each case on its own merits and exercises appropriate discretion after reviewing all the facts involved," an ICE spokesperson told The Hill in a statement Tuesday but declined to say whether the agency would be taking over the program from USCIS.

USCIS receives about 1,000 deferred action requests annually, mostly due to family or medical reasons. Most are not approved.

The Associated Press, which first reported the policy change, said it obtained USCIS letters sent to applicants in the Boston area and that the correspondence made no mention of ICE taking over the program. Instead, the letters ordered the immigrants to exit the U.S. in 33 days or face deportation, according to the AP.

Critics have denounced the policy change.

"This is a new low," Sen. Ed Markey (D-Mass.) told the AP. "Donald Trump is literally deporting kids with cancer."

The news follows an announcement earlier this month of a new "public charge" rule that will make it more likely for legal immigrants to be denied a green card if they use social services like food stamps and Medicaid. That rule, expected to go effect in October, is being challenged in court.

Updated at 3:16 p.m.