Relatives of the Christian victims of the crashed EgyptAir flight MS804 attend an absentee funeral mass at the main Cathedral in Cairo, May 22, 2016. Mohamed Abd El Ghany/Reuters

Republican Reps. Peter King of New York and Mike McCaul of Texas Sunday pointed to terrorism as the likely cause of last week’s crash of EgyptAir Flight 804 in the Mediterranean and said counterterrorism efforts should focus more sharply on airport workers.

But former US Airways pilot Chesley “Sully” Sullenberger, Homeland Security Secretary Jeh Johnson and former National Transportation Safety Board Chairman Mark Rosenker have each cautioned it’s too early in the investigation to draw any definitive conclusions.

EgyptAir Flight 804 disappeared from radar early Thursday after data transmitted from the aircraft indicated there was smoke in the plane. Before taking off from Paris for Cairo, the plane made stops in Eritrea and Tunisia.

“In light of recent events … it’s human nature to think of terrorism in the forefront,” Sullenberger, who shot to fame after landing a fully loaded passenger jet on the Hudson River following a bird strike, said on CBS’s “Face the Nation.” Citing other crashes, Sullenberger said accidents in the cruise portion of a flight can still happen despite advances in aviation safety.

King cited terrorism as the likely cause of the crash, noting the extent of the threat posed by the Islamic State group and other terrorist organizations, anger toward Egypt’s president and airport “insiders” who have access to planes. “Insiders at airports are a greater threat than passengers bringing bombs on the plane. They have access,” King said on CNN’s “State of the Union,” noting dozens of airport works with suspected terrorist sentiments recently were fired at Charles De Gaulle airport in France.

King admitted, however, the longer no terrorist group claims responsibility for the crash, the more likely the cause was a mechanical failure.

Sullenberger agreed the process of vetting airport employees needs to be tightened.

Johnson, on “Fox News Sunday,” turned aside a question on whether there was any terrorist chatter before the crash indicating something was imminent, saying it’s still early in the investigative process. He also pledged not to short-circuit security precautions at U.S. airports just because screening times are increasing.

McCaul, chairman of the House Homeland Security Committee, said on “Fox News Sunday” clearly “something catastrophic occurred.”

“Many signs do point to terrorism or an explosive device on the aircraft,” he said. “A window in the cockpit was breached, indicating it might have been blown out.”

Both presumptive presidential nominees Democrat Hillary Clinton and Republican Donald Trump said they believed terrorism was the cause.

Rosenker said on “Face the Nation” most of the facts surrounding the crash should be available within a month, and before any pronouncements can be made on the cause of the crash, “We need to understand the facts.”

“People can say what they wish to say but they will look ignorant” if they str at odds with what really happened,” Rosenker said.