Since the Obama administration began its controversial push to deport Central American immigrants who arrive here illegally, the number trying to enter the US has sharply declined, Homeland Security Secretary Jeh Johnson said Thursday.

“I know this has made a lot of people I respect very unhappy,” Johnson said, “But we must enforce the law in accordance with our priorities.”

Since the enforcement action began in late December, the number of unaccompanied children apprehended at the southwest border dropped 54 percent, and the number of those in families fell 65 percent, he said.

So far this month the numbers have remained low, a trend Johnson called encouraging.

“But it does not mean we can dial back our efforts,” he said.

Aggressive enforcement by agents of Immigration and Customs Enforcement brought protests last month from Sen. Bernie Sanders and more than 150 other members of Congress.

Rep. Luis Gutierrez, an Illinois Democrat, said the raids “sowed the seeds of terror throughout the immigrant community of the United States.”

But Johnson said DHS is also expanding the Refugee Admissions program for vulnerable men, women, and children fleeing the violence in Central America who qualify as refugees.

His remarks came in a speech in Washington outlining accomplishments by the Homeland Security department and his goals for the administration’s remaining days in office.

He said a system for detecting cyber attacks on federal government computers has been expanded, blocking more than 700,000 attempted intrusions.

And he said the deployment of additional Customs officers at 15 overseas airports resulted in stopping more than 10,700 people seeking to fly to the US who did not pass pre-clearance checks.

In response to the devastating results from a government test of domestic airport screening last May, Johnson said the Transportation Security Administration has required “back to basics” training for all TSA screeners, re-evaluated screening equipment, and increased the number of manual checks of passengers and their carry-on bags.

As a result, and because of the higher volume of air travel, “overall wait times have increased somewhat at airports, but we believe this is necessary for the public’s own safety,” he said.

TSA reported that its screeners checked 695 million passengers during the past fiscal year — three million more than the year before. They also screened 450 million pieces of checked baggage, the highest number in six years.