Homeland Security Secretary Jeh Johnson faced tough questions from Congress on Wednesday about a recent surge in illegal immigration, and agreed with lawmakers that a wave of unaccompanied children crossing illegally into the U.S. constitutes a "humanitarian crisis."

“Our current system is broken and unsatisfactory,” Johnson said in testimony before the Senate Judiciary Committee. “We have 11.5 million undocumented in this country. They aren’t going away.”

In recent months, America’s immigration policies have come under fire, heavily criticized by both Republicans and Democrats for creating a magnet.

Federal authorities say their budgets to police the borders have been strained as illegal immigrants – mostly women and children – from Central America cross the border. Federal officials have lately been transporting hundreds from overburdened facilities in Texas to Arizona and other states.

At the hearing, Alabama Republican Sen. Jeff Sessions criticized the country’s current policies and said it sent a signal to everyone in the world: “Come here by a certain age and you’ll get amnesty.”

The Department of Homeland Security is the federal agency responsible for deporting illegal immigrants. In its 2015 budget overview, the DHS has asked for $229.1 million to help with the costs of deportation.

Addressing a related concern of lawmakers, Johnson said government attorneys are reviewing the criteria for how the Obama administration releases some criminal immigrants facing deportation while detaining others.

Johnson told the Senate Judiciary Committee on Wednesday that lawyers will review federal policies based on a Supreme Court ruling that requires the government to release immigrants convicted of crimes if the U.S. can't send them to their home country within six months. Johnson said he wants to know whether the government can hold them longer as threats to national security or public safety. He also said he wants more-senior officials to review and approve such releases.

Last month, the Obama administration acknowledged it had released more than 36,000 criminal immigrants living in the country illegally, including those accounting for 193 homicides and 426 sexual assaults.

In late May, Obama also delayed the review of deportation policies until the end of summer in hopes Congress would approve a comprehensive overhaul. The plan, as of now, is to reveal the results before lawmakers take their summer recess in August.

Tuesday’s surprise primary defeat of House Majority Leader Eric Cantor in Virginia led some political analysts to theorize that any hopes for a substantial immigration bill to pass this year had been shelved.

The White House, though, was quick to push back with senior adviser Dan Pfeiffer tweeting, “Cantor’s problem wasn’t his position on immigration reform, it was his lack of a position.”