– With Al-Qaida militants surging in the Middle East and North Africa, U.S. law enforcement officials are increasingly concerned about efforts to recruit and radicalize American citizens by drawing them to the region and sending them back to this ­country to carry out attacks.

FBI Director James B. Comey calls the threat one of the bureau’s top priorities and said the agency is working to identify and track U.S. residents who travel overseas, embrace Al-Qaida ideology and return to the United States.

“We are focused on trying to figure out what our people are up to, who should be spoken to, who should be followed, who should be charged,” Comey said in a recent meeting with reporters. “It’s something we are intensely focused on.”

Rep. Mike McCaul, R-Texas, chairman of the House Homeland Security Committee, said Al-Qaida, which has turned into a number of splinter groups, is just as ominous a threat as it was on Sept. 11, 2001.

“Al-Qaida is not on the run, but is in fact growing in strength at an alarming rate across the Middle East and North Africa,” he said last week.

Minnesota Somalis tracked

Federal law enforcement officials said they are tracking other U.S. residents traveling abroad, specifically Somali Americans from Minnesota who have gone to fight in that country.

They also are watching several individuals identified soon after the Sept. 11 attacks, such as half a dozen men from the ­Buffalo suburb of Lackawanna, N.Y., who trained at an Al-Qaida facility in Afghanistan.

Comey said these suspects are always the most difficult to identify and stop. He said it is all the more challenging today because Al-Qaida has been “metastasizing” into splinter groups in Iraq, Syria and Libya.

Although the FBI previously had “great success” against Al-Qaida in the group’s traditional Afghanistan-Pakistan region, Comey said, “in the ungoverned or poorly governed spaces in Africa and around the Middle East, we see a resurgence of Al-Qaida affiliates.”

Two U.S. cases last year

Two cases of radicalized Americans surfaced last year.

Nicole Lynn Mansfield, a nurse from Flint, Mich., died in May while fighting with anti-government militants in Syria.

The other was Eric Harroun, a former U.S. Army private from Tucson, Ariz., who pleaded guilty in September to conspiracy to violate arms-control laws after fighting in Syria alongside a branch of Al-Qaida.

Two others in recent years were radicalized in Pakistan, and then returned to the U.S. and came dangerously close to carrying out bombings in New York. Najibullah Zazi, an Afghan American, schemed to blow up the subway with backpack bombs, and Faisal Shahzad, an American born in Pakistan, attempted to detonate a car bomb in Times Square.

Zazi was arrested in 2009 and admitted he was “recruited” by Pakistani militants to hit the transit system with a series of suicide bombs. He pleaded guilty and was facing life in prison, but he was later reportedly moved to a secret location.

Shahzad was arrested in 2010 after trying to detonate a bomb in Times Square. He pleaded guilty and admitted he had received training in Pakistan. He was sentenced to life in prison.