Updated

Homeland Security Secretary Jeh Johnson is asking for an internal review of the Obama administration's release of tens of thousands of immigrants in the country illegally who were convicted of crimes and facing deportation. He's telling lawmakers he wants a deeper understanding of the issue.

Federal data published this month showed that the Homeland Security Department released 36,007 convicted criminal immigrants last year who are facing deportation, including those accounting for 193 homicide and 426 sexual assault convictions. The immigrants nearly all still face deportation and are required to check in withimmigration authorities while their deportation cases are pending.

News of the releases, which came amid an ongoing review of the Obama administration's deportation policies, incensed Republican lawmakers who contend that President Barack Obama has not properly enforcedimmigration laws. The House Judiciary Committee chairman, Rep. Bob Goodlatte, R-Va., said the releases "needlessly endanger Americans' lives."

In testimony sent to Congress ahead of a hearing by the committee Thursday, Johnson said he was "committed to enforcing our immigration laws in a manner that best promotes and ensures national security, public safety and border security." He said he has asked for a "deeper understanding" of the releases, and he pledged to continue to work with U.S. Immigration and Customs Enforcement to ensure public safety.

Johnson said many of the releases were directed by an immigration judge or were prompted by other legal requirements. His written testimony did not provide additional details.

The White House said this week it asked Johnson to delay completing his review of deportation policies until the end of the summer. It was a move aimed at salvaging hope for Congress to act on an immigration bill before November's midterm elections.