A second high-ranking official in a two-month-old federal office that oversees immigration detention policy and planning has left the government, sources say.

Cree Zischke, tasked with addressing detainee health care issues for Immigration and Customs Enforcement’s Office of Detention Policy and Planning, departed just weeks after her boss, Dr. Dora Schriro, left ICE in late September to become commissioner of New York City’s jails.

“I am no longer with the ICE Office of Detention Planning and Policy (sic),” she wrote in an out-of-office auto-reply received on Oct. 14 by the Center for Investigative Reporting.

Sources this week confirmed that Zischke is no longer with ICE, an agency of the Department of Homeland Security, and has returned to the private sector. Calls seeking comment from Zischke were not returned.

Zischke came to ICE from the Arizona Department of Corrections, where she directed a program that addressed health and mental health services, among other concerns, according to her resume posted on LinkedIn, a business-oriented social networking Web site.

She followed Schriro, her former boss in Arizona, to Washington, D.C., leaving her prison post in March. Before directing the ICE detention policy and planning office, Schriro had advised Homeland Security Secretary Janet Napolitano on immigration detention. Before that, she ran Arizona’s prisons when Napolitano was governor of the state.

The New York Times reported in September that Schriro left DHS because of “the needs of a sick family member in New York, not any policy disagreements with the administration.”

Schriro left the position a little more than a month into her job as the director of the new ICE office, which was unveiled in early August. Phyllis A. Coven, who has spent 17 years in federal government, most recently with U.S. Citizenship and Immigration Services, replaced Schriro as the office’s acting director.

The decision — and timing — of both departures surprised advocates, Congressional staffers and other government employees, and left many speculating about the reasons.

Megan Bremer, managing attorney of the Pennsylvania Immigration Resource Center, which offers legal services to detained immigrants in York, Penn., said advocacy groups like hers were optimistic about discussions over reform with Schriro and Zischke, and hoped the same efforts would continue.

“Folks in the Department of Homeland Security, like Cree, were really reaching out to advocates, sitting down across the table from us and listening,” she said. “PIRC is very disappointed that the kind of people who have the ability to create partnerships are leaving the government during this critical period of reform.”

Immigration advocates had put stock in Schriro to overhaul the nation’s immigration detention system, first as a special advisor to Secretary Napolitano, then as the new office’s first director. After Schriro left advocates hoped that Zischke would continue what her former boss had started.

In early October Schriro released a 35-page report that outlined recommendations and potential reforms to the immigration detention system, which uses more than 300 facilities around the country to hold more than 30,000 detainees on any given day.

Among the announced reforms are new classification systems for detainees, including those with special medical needs, greater oversight of detention facilities and contracts, and an expansion of alternatives to detention.

Andrew Becker is a reporter for Reveal, covering border, national and homeland security issues, as well as weapons and gun trafficking. He has focused on waste, fraud and abuse – with stories ranging from border corruption to the expanding use of drones and unmanned aerial vehicles, from the militarization of police to the intersection of politics and policy related to immigration, from terrorism to drug trafficking. Becker's reporting has appeared in The Washington Post, the Los Angeles Times, The New York Times, Newsweek/The Daily Beast and on National Public Radio and PBS/FRONTLINE, among others. He received a master's degree in journalism from UC Berkeley. Becker is based in Reveal's Emeryville, California, office.