A police dispatcher in Colorado listened helplessly on the phone on Tuesday to what authorities believe was at least a triple murder-suicide.

Weld County Sheriff's spokesperson Tim Schwartz told reporters that a woman called police at around 4 a.m. on Tuesday morning, gave her address and then said, "No, no, no." The dispatcher then heard a number of gunshots, according to CNN.

At least 4 bodies were found when law enforcement entered the home east of Longmont. Initial reports had said that five people were found at the scene.

Authorities told KMGH-TV that three adults had apparently been murdered by a fourth adult who then killed himself with a handgun.

"We heard bang, bang, bang and a scream," one neighbor recalled to the Denver station.

Recordings provided by RadioReference.com indicated that the gunman had been speaking to the Weld County Sheriff's Department before committing suicide.

"Weld County advising that they have an open line into the residence," a dispatcher said at around 4:22 a.m. "They had a caller advise that he had shot multiple people inside the house, family members and a light."

Update (11::00 a.m. ET): "I don't recall the last time this happened, anything like this even," Schwartz said at a press conference later in the morning. "This has sparked interest all over the United States so far."

Watch this video from KMGH, broadcast Dec. 18, 2012.