PROVIDENCE, R.I. (AP) — A person of interest detained after a Brown University shooting that killed two students and injured nine will be released after an investigation took law enforcement authorities in a “different direction,” officials said Sunday night.

The disclosure, made at a hastily convened late night news conference, represents a stunning turn of events in an investigation into killings that rattled the Ivy League campus and came more than 12 hours after officials had announced that they had taken a person into custody in connection with the attack.

The release means that whoever is responsible for the killing may remain at large.

“We know that this is likely to cause fresh anxiety for our community,” Mayor Brett Smiley said.

The attack Saturday afternoon set off hours of chaos across campus and surrounding Providence neighborhoods as hundreds of officers searched for the shooter and urged students and staff to shelter in place. The lockdown, which stretched into the night, was lifted early Sunday, but authorities had not yet released information about a potential motive.

On Sunday morning, officials took a person into custody that two people familiar with the matter identified as a 24-year-old man from Wisconsin. That individual, whose name was never released by authorities, is now being released.

“I’ve been around long enough to know that sometimes you head in one direction and then you have to regroup and go in another and that’s exactly what has happened over the last 24 hours or so,” said Attorney General Peter Neronha.

Col. Oscar Perez, the Providence police chief, said Sunday afternoon that no one has been charged yet. Perez, who also said no one else was being sought, declined to say whether the detained person had any connection to Brown.

The person was taken into custody at a Hampton Inn hotel in Coventry, Rhode Island, about 20 miles (32 kilometers) from Providence, where police officers and FBI agents remained Sunday, blocking off a hallway with crime scene tape as they searched the area.

The shooting occurred during one of the busiest moments of the academic calendar, as final exams were underway. Brown canceled all remaining classes, exams, papers and projects for the semester and told students they could leave campus, underscoring the scale of the disruption and the gravity of the attack.

As police scoured the area for the shooter, many students remained barricaded in rooms while others hid behind furniture and bookshelves. One video showed students in a library shaking and wincing as they heard loud bangs just before police entered the room to clear the building.

University President Christina Paxson teared up while describing her conversations with students both on campus and in the hospital.

“They are amazing and they’re supporting each other,” she said at a news conference. “There’s just a lot of gratitude.”

The gunman opened fire inside a classroom in the engineering building, firing more than 40 rounds from a 9 mm handgun, a law enforcement official told AP. Two handguns were recovered when the person of interest was taken into custody and authorities also found two loaded 30-round magazines, the official said. One of the firearms was equipped with a laser sight that projects a dot to aid in targeting, said the official, who was not authorized to discuss the investigation publicly and spoke to AP on the condition of anonymity.

One student of the nine wounded students had been released from the hospital, said Paxson. Seven others were in critical but stable condition, and one was in critical condition.

Durham Academy, a private K-12 school in Durham, North Carolina, confirmed that a recent graduate, Kendall Turner, was critically wounded. The school said her parents were with her.

“Our school community is rallying around Kendall, her classmates, and her loved ones, and we will continue to offer our full support in the days ahead,” the school said.