WASHINGTON (CBSDC/AP) — A former CIA operative believes the married couple who opened fire and killed 14 people at the Inland Regional Center in San Bernardino deployed “ISIS tactics.”

Robert Baer, CNN intelligence and security analyst, believes 28-year-old Syed Farook and his 27-year-old wife Tashfeen Malik received combat training.

“The tactics that they adopted in taking down this place were exactly ISIS tactics,” Baer told CNN. “Now I’m not saying ISIS was behind this, inspired it, they haven’t claimed it or anything like that, but the tactics suggest they were taught in the Middle East or they simply were on websites and got some sort of training. These are not people that just got mad at their employer and shot the place up. I just don’t see that right now,” Baer explained to CNN.

Farook, who worked for San Bernardino County’s Health Department, was at the company’s holiday party at the regional center when he abruptly left, authorities said. He then returned with his wife, wearing tactical clothing and armed with assault rifles and extra magazines of ammunition.

The two were killed in a shootout with police following the shooting. Baer said the couple was “ready to die.”

“What disturbs me is this was a military assault. The fake pipe-bomb that was thrown out of the car to break contact with the police; the remote-controlled detonated device left inside the building; two shooters; a lot of ammunition. These people had some training, some sort of commitment to this,” Baer told CNN. “And also it’s clear to me that when they decide to take on the police and fire back on them that they were ready to die. They looked like they were martyrs to me. And I’ll go out on a limb, I’m convinced right now until proven otherwise, that this was international terrorism. … Right now this is too well planned, too well coordinated. As I said, classic military assault — speed, surprise, extreme violence at the objective. It just fits those characteristics and not a workplace shooting.”

President Barack Obama said Thursday that it’s possible the shooting was an act of terrorism, but it’s still too soon to know. The FBI has taken over the investigation.

Farook’s brother-in-law told CBS News the couple was married for two years and had a 6-month-old daughter. Baer suspects Malik “was a believer.”

“It certainly adhered to the Islamic State’s propaganda in some way. I think there may be evidence that we’re going to have to wait and see, but I have never seen a workplace shooting where the wife comes in, drops the baby off in advance, and then goes and shoots the place up and then gets in a gun fight with the police. I’ve never heard of that, ever.”

Farook was born in the U.S. to a Pakistani family, was raised in Southern California and had been a San Bernardino County employee for five years, according to authorities and acquaintances. San Bernardino Police Chief Jarrod Burguan said he had no information on Malik’s background. Relatives said Farook had traveled to Saudi Arabia to meet his wife.

Police and federal agents for a second day searched a home in neighboring Redlands, about 7 miles from the massacre at the Inland Regional Center. Investigators didn’t immediately say if the couple had lived there. Public records show it may be the home of a Farook family member.

Residents told KABC-TV Redlands is a sleepy town and expressed shock that the killers might be their neighbors.

The attackers invaded the center about 60 miles east of Los Angeles around 11 a.m., opening fire in a conference area where county health officials were having an employee banquet. Farook attended the banquet, then left, then returned with murderous intent.

“They came prepared to do what they did, as if they were on a mission,” Burguan said.

Co-worker Patrick Baccari said he was sitting at the same table as Farook, who suddenly disappeared. Baccari said that when the shooting started, he took refuge in a bathroom and suffered minor wounds from shrapnel slicing through the wall.

The shooting lasted about five minutes, he said, and when he looked in the mirror he realized he was bleeding.

“If I hadn’t been in the bathroom, I’d probably be laying dead on the floor,” he said.

Baccari described Farook as reserved and said he showed no signs of unusual behavior. Earlier this year, he traveled to Saudi Arabia, was gone for about a month and returned with a wife, later growing a beard, Baccari said.

The couple dropped off their 6-month-old daughter with relatives Wednesday morning, saying they had a doctor’s appointment, Hussam Ayloush, executive director of the Council on American-Islamic Relations, said after talking with family.

“We don’t know the motives. Is it work, rage-related? Is it mental illness? Is it extreme ideology? At this point, it’s really unknown to us, and at this point it’s too soon to speculate,” Ayloush said.

Co-workers told the Los Angeles Times that Farook was a devout Muslim but didn’t talk about religion at work.

Farhan Khan, who is married to Farook’s sister, told reporters that he last spoke to his brother-in-law about a week ago. Khan condemned the violence and said he had “absolutely no idea” why Farook would do such a thing.

Seventeen people were wounded, according to authorities. Ten were hospitalized in critical condition, and three in serious condition, Fire Chief Tom Hannemann said.

About four hours after the morning carnage, police hunting for the killers riddled a black SUV with gunfire in a shootout 2 miles from the social services center in this Southern California city of 214,000 people.

Farook and Malik were found with assault rifles and semi-automatic handguns, and were wearing “assault-style clothing” with ammunition attached, authorities said.

Three explosive devices — all connected to one another — were found at the social services center, police said.

Federal authorities said the two assault rifles and two handguns used in the violence had been bought legally, but they did not say how and when they got into the attackers’ hands.

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