Homeland Security Secretary Jeh Johnson warned Thursday that terror groups remain focused on targeting aviation, on the heels of an attempted bombing last week in Somalia – and after the top U.S. intelligence official warned that the Islamic State will try to attack the U.S. this year.

Johnson, delivering his final State of Homeland Security address, stressed that his department is moving to reduce the number of access points to airport employees to reduce any insider threat.

“We have the ability, through airlines, through our relationship with other countries, to put out guidelines that influence the behavior of airport authorities and airport security at overseas airports,” he said. “In particular, last point of departure airports, and those are mostly in Europe. Some are in the Middle East.”

Johnson said passengers and staffers at airports with direct flights to the U.S. now face extra screening, and that the feds can stop certain flights from landing in the U.S. if those airports fail to meet new standards.

Such measures were also added at regional airports, he said, citing the November bombing of a Russian passenger jet that had taken off from that Red Sea resort of Sharm-e-Sheikh, Egypt. ISIS claimed responsibility for that attack.

Somalia faces an insurgency from the Islamic extremist group al-Shabab, which has carried out deadly attacks in Somalia and neighboring countries.

A suspected suicide bomber apparently used a laptop to blow a gaping hole in a Daallo Airlines jet on Feb. 2, forcing an emergency landing in Mogadishu, according to investigators who said the attacker was apparently sucked out of the plane to his death. Two people were reported hurt.

At least 20 people are under arrest in connection with the bombing, including two men caught on surveillance video handing the laptop to the suspect.

The video of the apparent security lapse at the airport fits with the description of lax security by the jet's pilot. "The security is zero," Vlatko Vodopivec told The Associated Press.

Director of National Intelligence James Clapper told the Senate Select Committee on Intelligence Tuesday that ISIS will very likely try to attack the U.S. with its own trained operatives. Johnson did not say whether he agreed with that assessment, but did indicate that Homeland Security is working to identify potential attackers who "self-radicalize."

He added, "It is almost always the case that when somebody self-radicalizes, there is somebody in a position to know about it. And the more we build bridges to communities, Muslim communities in particular, the better off I think we will be."

Johnson cited the December terror attack in San Bernardino, Calif. that killed 14 people. Local FBI agents reportedly did not receive indications beforehand that attackers Syed Farook and Tashfeen Malik were plotting their rampage.

"The United States will almost certainly remain at least a rhetorically important enemy for most violent extremists in part due to past and ongoing U.S. military, political, and economic engagement overseas," Clapper told lawmakers.

Fox News' Catherine Herridge and The Associated Press contributed to this report.