U.S. intelligence officials fear ISIS terrorists are spreading across Europe and beyond by printing their own fake Syrian passports — a terrifying prospect that has one expert warning their fighters may already be here.

“It’s very scary,” Northeastern University professor Max Abrahms said of reports indicating the barbaric jihadists are creating their own falsified Syrian passports as a means of spreading its fighters around the world.

“There’s a real sense that our porous borders are posing a very real terrorist threat to the United States,” Abrahms told the Herald. “At least two of the perpetrators of the Paris attacks got into the country through Greece using fake identification — and of course you have Tashfeen Malik in San Bernardino, who got into the country by misrepresenting herself on her fiancee visa.”

U.S. Rep. Stephen F. Lynch said he has been briefed on the ISIS passport threat, adding both the FBI and federal immigration officials have confirmed the horrifying prospect.

“This is a reason for very high concern, especially with the number of refugees piling into Germany and France,” the South Boston pol said.

Lynch said ISIS fighters got their hands on blank passports and the machine needed to print them when they overran Deir ez-Zour in eastern Syria more than a year ago.

“They can put together a very high quality counterfeit passport,” said Lynch.

Gov. Charlie Baker, who has voiced concerns about the vetting process for Syrian refugees entering the U.S., said yesterday he “certainly” will ask federal officials about concerns that ISIS has been printing false passports.

“There are bipartisan concerns about the vetting process. Congressman Lynch, Congressman (James) McGovern, Congressman (Bill) Keating, Sen. (Ed) Markey, Gov. (Maggie) Hassan in New Hampshire, myself and many others have expressed concerns about the vetting process with respect to refugees,” Baker said, adding that the possibility that ISIS has been manufacturing fake passports is “certainly something that I will ask about.”

FBI Director James Comey addressed the risk while speaking before the Senate Judiciary Committee on Wednesday, admitting that “the intelligence community is concerned that they have the capability to manufacture fraudulent passports, which is a concern in any setting.”

Abrahms said the revelation could make it harder for President Obama to sell American citizens on the importance of accepting Syrian refugees.

“Now you have credible reports that the Islamic State is printing effective, counterfeit Syrian passports, and that the people there have already dispersed to numerous other countries — including the United States — that’s a real cause for concern,” Abrahms said. “It makes Obama’s job tougher in terms of championing absorbing Syrian refugees at a time when the majority of Americans already don’t support that policy.”

Baker said state officials have been “having very positive, I believe, and constructive discussions with folks at the State Department and National Homeland Security.”

“They’ve answered many of the questions we’ve raised, we’ve asked other questions that they need to get back to us on,” Baker said. “But as long as they continue to share information when we ask, then I’m going to consider that to be progress.”

Though he said he still wants more information about the vetting process for refugees coming to the United States from Syria, Baker also stressed “Massachusetts has always been an active and engaged participant in the refugee resettlement — it’s part of who we are and part of our heritage and I believe we should continue to be a positive and constructive participant.”