Investigators seek older video that might show the Brown campus shooter days before the attack

"I believe that this is probably the most intense investigation going on right now in this nation" Providence's police chief, Col. Oscar Perez, said at a Wednesday news conference, noting that investigators have collected a lot of crime scene evidence.

Although Brown President Christina Hull Paxson said there are 1,200 cameras on campus, the attack, which killed two students and wounded nine others, happened in a first-floor classroom in an older part of the engineering building that has "fewer, if any" cameras, Rhode Island Attorney General Peter Neronha noted. Investigators also believe the shooter entered and left the building through a door that faces a residential street bordering campus, which might explain why the cameras Brown does have didn't capture footage of the person.

The lack of campus video of the shooter led President Donald Trump to accuse the Ivy League school of being unprepared, posting Wednesday on Truth Social: "Why did Brown University have so few Security Cameras? There can be no excuse for that. In the modern age, it just doesn't get worse!!!"

Where the investigation stands

Investigators have described the person they're seeking as about 5 feet, 8 inches (173 centimeters) tall and stocky, but they've given no indication that they are close to zeroing in on their identity.

The attacker's motives also remain a mystery, and Neronha batted away questions about what they might be, saying Tuesday, "That is a dangerous road to go down."

Authorities have been canvassing the surrounding neighborhoods and have received about 200 tips, and Neronha defended the investigation as going "really well" as he pleaded for patience.

"We're all over the place. If a tip tells us we need to go down to Connecticut, we're going down to Connecticut. If a tip comes in and tells us that we got to go to Boston, we're going to Boston," Perez said Wednesday.

But the timing of the attack, coming just before the winter break, could complicate the investigation, as remaining classes and exams were canceled after the shooting and many students have already gone home.

The investigation also comes as Boston-area police search for the person who killed a Massachusetts Institute of Technology professor earlier this week. That attack happened in the professor's home, and the FBI said it had no reason to think the two attacks were linked.

Separately, Providence police on Wednesday released a new photo of a separate individual who they said was in "proximity of the person of interest" and asked the public to help identify that person so they could speak with them. The person in the new photo is wearing dark pants and a blue jacket, and carrying a light tan bag.

Campus security comes under scrutiny

The attack and shooter's escape have raised questions about campus security.

Paxson said Brown has two security systems. One, which is activated in times of emergency, sent out text messages, phone calls and emails that reached 20,000 people. The other features three sirens across the campus and was not activated Saturday, a decision Paxson defended because doing so would have caused people to rush into buildings, including the one where the shooting was happening.

"So that is not a system we would ever use in the case of an active shooter," she said.

Brown's website says the sirens can be used when there is an active shooter, but Paxson said it "depends on the circumstances" and the location of the shooter.

A city on edge

With the shooter still at-large, Providence remained tense Wednesday as additional police were stationed at city schools to reassure worried parents that their kids would be safe. Some schools canceled afterschool activities and field trips.

Prior to the shooting, nearly 1,600 Providence residents were registered to receive texts through a city text alert service. According to the city, 760 new accounts have been created since Sunday, bringing the total number of people registered to receive texts to more than 2,300 as of late Tuesday.

Brown also cautioned people to refrain from accusing people online of having any link to the attack, after it said such speculation led to a student being doxed — their identifying information was posted.

"Accusations, speculation and conspiracies we're seeing on social media and in some news reports are irresponsible, harmful, and in some cases dangerous for the safety of individuals in our community," the school said in a statement.

And the police chief on Wednesday asked the public to stop circulating AI-generated images being shared on social media.

Honoring the victims

About 200 people gathered at a campus church service Tuesday to honor the victims, including Ella Cook and MukhammadAziz Umurzokov, the two students who died.

Cook was a 19-year-old sophomore from Alabama who was very involved in her church and served as vice president of the Brown College Republicans.

Umurzokov was an 18-year-old freshman from Virginia whose family immigrated to the U.S. from Uzbekistan and who hoped to go to medical school one day.

Mayor Brett Smiley said Wednesday that a third wounded student had been discharged, leaving five still hospitalized in stable condition and one in critical condition.