Washington, Jun 18 (IANS/EFE): The director of US Immigration and Customs Enforcement (ICE), John Morton, said Monday that he will leave his post next month to work in the private sector after four years at the head of the agency.

"I am extremely proud of what we have accomplished together during that time and look with awe on the incredible progress ICE has made as an agency," he said in a letter directed to ICE employees.

Morton became ICE director in May 2009 after having worked for 15 years in the Justice Department.

In his letter, Morton emphasized the evolution of ICE into an "innovative, leading force in federal law enforcement".

One critic, however, said Morton's tenure had witnessed "a massive increase in the deportations of immigrant families".

Morton's departure presents "a new opportunity" for the priorities of immigration control to align themselves with reason and humanity, Kica Matos, the director of immigrants' rights and racial justice at the Center for Community Change, said.

She asked Homeland Security Secretary Janet Napolitano and President Barack Obama to name a person who better reflects the government's "priorities" to replace Morton.