What to know about the search for the Brown University shooter

PROVIDENCE, R.I. — The investigation into the Brown University mass shooting shifted Thursday when authorities said they were looking into a connection between the shooting and an attack two days later near Boston that killed a professor from Massachusetts Institute of Technology.

The attacker at Brown killed two students and wounded nine others on Saturday. Some 50 miles (80 kilometers) away MIT professor Nuno F.G. Loureiro was killed Monday night in his home in the Boston suburb of Brookline.

Here are some answers to questions about the attacks and investigations:

What is the potential connection between the Brown and MIT killings?

Authorities have not divulged much information yet. Three people familiar with the matter who were not authorized to discuss an ongoing investigation and spoke on condition of anonymity confirmed the shift in investigation. Two of the people said investigators had identified a person of interest in the shootings and were actively seeking that individual.

The FBI previously said it knew of no links between the cases.

What is the latest on the Brown investigation?

Frustration is mounting in Providence that the person behind the Brown attack managed to get away and that a clear image of their face has yet to emerge.

Authorities have released several security videos of a person they think might have carried out the Brown attack. They show the individual standing, walking and even running along the streets, but their face is masked or turned away in all of them.

The state attorney general said the wing of the engineering building where the attack happened has few ''if any'' cameras, and investigators believe the shooter entered and left through a door that faces a residential street bordering campus. The building is on the edge of campus, which might explain why the cameras Brown does have didn't capture footage of the person.

Who was the MIT professor, and why was he killed?

Loureiro, 47, who was married, joined MIT in 2016 and was named last year to lead the school's Plasma Science and Fusion Center, where he worked to advance clean energy technology and other research. The center, one of MIT's largest labs, had more than 250 people working across seven buildings when he took the helm. He was a professor of physics and nuclear science and engineering.

Why were Brown, that building and that classroom attacked?

We still don't know. Although police said this week that they believe Brown was purposefully targeted and that the videos suggest the masked person had been casing the building, no one has taken credit for the attack and investigators apparently still hadn't identified a suspect as of Thursday.

The investigation was taking place as Brown was sending out early decision notifications.

How many students were in the Brown classroom?

Police say they still don't know. The finals study session was for a ''Principles of Economics'' course that attracts hundreds of students each semester, but police are still tracking down how many may have been in the room.

The two students who were killed and the nine others injured were studying for a final in a first-floor classroom in an older section of the engineering building when the shooter walked in and opened fire.

Those killed were 19-year-old sophomore Ella Cook and 18-year-old freshman MukhammadAziz Umurzokov. Cook, whose funeral is Monday, was active in her Alabama church and served as vice president of the Brown College Republicans. Umurzokov's family immigrated to the U.S. from Uzbekistan when he was a child, and he aspired to be a doctor.

As for the wounded, six were in stable condition Thursday, officials said. The other three were discharged.

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