It was Thursday morning when investigators definitively determined the same individual opened fire on a study group at Brown University and, two days later, murdered an MIT professor — raising fears among law enforcement officials that the killer may have had other intended targets, according to the top federal law enforcement official in Boston.

“We had no idea if he had a hit list and these were just the first two stops on his tour,” Leah Foley, the United States Attorney for the District of Massachusetts, told ABC News on Friday.

Foley said that the suspect, Claudio Manuel Neves Valente, was found dead in the New Hampshire storage unit with two 9mm Glock firearms equipped with green laser sights, five magazines with nearly 200 rounds of ammunition and nearly $900 in cash. In his car, investigators said they found more ammunition and body armor.

“This was highly premeditated and he was definitely equipped for the mission that he sought out to do,” Foley said.

Neves Valente, 48, died from a self-inflicted gunshot wound, police said.

On Friday, an autopsy was underway to determine how long the suspect had been dead by the time his body was found. Ballistics tests and DNA tests were underway.

Investigators were also searching through the contents of three USB thumb drives found in the suspect’s car to see if they contained clues about a motive. It is unclear at this time if the suspect had any other potential targets, according to people familiar with the investigation.

Foley said investigators believe Brown University and the MIT professor — Nuno F.G. Loureiro — were intentional targets, but they do not know why.

“I don’t know that even if he had explained why, that that would be an answer that is satisfactory to anyone,” Foley said. “He was evil.”

The possibility that the killer could have struck again infused the manhunt with new urgency. Federal agents fanned out across four New England states and posted up at airports in Boston and Hartford.

“We had no idea if he was going to act again in New England or try to leave New England,” Foley said.

Neves Valente had already switched license plates once, according to authorities. In the car, investigators said they found another expired plate.

The suspect was a former Brown graduate student who attended the school some 25 years ago, school officials said. He had enrolled as a Ph.D student in Brown’s physics program in 2000 and attended for less than a year, before going on a leave of absence and then withdrawing.

Neves Valente and Loureiro were both Portuguese nationals and had attended the same physics engineering program at Instituto Superior Técnico in Lisbon, the school confirmed to ABC News.