The New Haven Police Department announced two major updates to the investigation of a rogue phone call made on November 25, which led to an hours-long, campus-wide lockdown and search for a gunman on Yale’s grounds.

In a press release issued at 4:43 p.m. on Monday, NHPD spokesman David Hartman said that, on Friday, police identified one person of interest in the case. Though Hartman did not elaborate on the person’s potential role in the incident, he did say that the person is currently in police custody on two arrest warrants that are separate from the lockdown case. Hartman also said that the NHPD has collaborated with the Federal Bureau of Investigation and the Yale Police Department daily since the incident, which occurred during the University’s November recess.

“Investigative resources were mobilized quickly and have stayed the course since that Monday morning in an effort to bring the person responsible to justice,” NHPD Chief Dean Esserman said in the press release.

The other finding announced by police on Monday was the continued search for a woman that investigators have identified as a potential witness. Hartman included pictures of the woman, who was seen in the 300 block of Columbus Avenue around the time the caller, a male, used a nearby phone booth to tell New Haven Police dispatchers that his roommate had a gun and plans to open fire on campus.

“It is our belief the woman… may be able to provide valuable information to Investigators,” Hartman said in the release. “This individual is urged to contact Detectives.”

Hartman also said that police are withholding the woman’s identity.

YPD Chief Ronnell Higgins was also quoted in the release, where he spoke to the need to respond to threats of a potential campus shooting with urgency.

“The episode was extremely disruptive to those of us on campus and to anyone in the downtown area, and generated understandable anxiety and concern,” Higgins said. “We are fortunate that no one was hurt, but it is a reminder that in today’s environment we must, and will continue to, take every threat seriously.”

The investigation has also cleared “several” suspects of involvement, according to the release.