Chad Wolf was confirmed to be the new acting secretary of Homeland Security on Wednesday, as a high rate of turnover continues to disrupt the agency’s top ranks with several recent leaders serving mainly in temporary roles.

Wolf, now the fifth DHS chief in less than three years since President Donald Trump took office, succeeds Kevin McAleenan, who served as acting secretary since April before resigning last month.

DHS has had a difficult time filling its high-level positions since the agency was established in 2002.

Two Senate confirmed DHS secretaries and one acting chief served under President Barack Obama. President George W. Bush also had three DHS heads after the agency was created under his administration post 9/11.

In the debate over Trump’s aggressive crackdown on immigrants, Democrats have been sharply critical of the agency, which oversees U.S. immigration enforcement and policy implementation.

“President Trump is intentionally circumventing Congress in order to install temporary leadership at DHS to further his cruel agenda against immigrant families and the Latino community,” Congressman Joaquin Castro said Wednesday.

As Wolf was elevated to the cabinet-level position, U.S. Citizenship and Immigration Services — a subsidiary of DHS — unveiled a new plan to withhold work permits from asylum seekers who cross the border between ports of entry.

“Illegal aliens are gaming our asylum system for economic opportunity, which undermines the integrity of our immigration system and delays relief for legitimate asylum seekers in need of humanitarian protection,” acting USCIS Director Ken Cuccinelli said, after announcing the new rule.

A record-setting spike in illegal crossings occurred over the past year as immigration authorities blocked asylum requests at legal ports of entry. An enforcement procedure known as “metering” has restricted legal options for unauthorized immigrants waiting at ports since 2016. The practice has likely prompted more illegal crossing attempts, according to federal government inspectors.

Felons and those guilty of certain misdemeanors, including driving under the influence, would also be ineligible for work permits under the new USCIS proposal.

Cuccinelli was asked at a Senate hearing today about why the employer verification systems don’t always stop unauthorized immigrant labor. Pointing to the recent ICE raids at several Mississippi food processing plants where E-verify systems largely failed, the acting director said employers have started facing new “consequences” for not fully complying.

USCIS in September scrapped a requirement that the agency issue work permits within 30 days of receiving a valid application.

The new proposal revealed Wednesday would allow the agency to take more time to issue the forms.

Cuccinelli is reportedly under consideration to serve in the number two position at DHS as Wolf’s deputy.

CNN first reported the news of his possible role change.