Carl Drega was born on January 19, 1935, in New Haven, Connecticut. His parents were Polish immigrants. Growing up, he faced the challenges that many immigrant families encounter. He claimed to have served in the U.S. military during the Korean War, but records of this service are hard to confirm.

After his time in the military, Drega worked in construction. He lived in Manchester, New Hampshire, before moving to Bow, New Hampshire. Drega and his wife, Rita, built their home together from 1969 to 1970. Sadly, in 1971, Rita was diagnosed with cancer. She passed away in 1972, which had a significant impact on Drega's life.

In the 1970s, Drega began to have conflicts with government officials. These disputes started when he wanted to use tar paper to side his vacation house in Columbia, New Hampshire. The house was located on the banks of the Connecticut River. In 1981, Drega reported that a rainstorm caused serious erosion on the riverbank. He attempted to fix this damage by dumping and packing dirt, which he believed would restore his land. However, state officials said he was trying to change the river's course.

Over the years, Drega's issues with local authorities grew. In 1995, he confronted town selectman Vickie Bunnell and a tax assessor at his property. During this incident, Drega fired shots into the air to scare them away. Following these conflicts, he bought a Colt AR-15 rifle and an armored vest. He equipped his property with electronic noise and motion detectors. These actions demonstrated his increasing tension with local officials.

On August 19, 1997, Carl Drega shot and killed four people in New Hampshire. The first victim was New Hampshire state trooper Scott Phillips. Phillips stopped Drega for having too much rust on his pickup truck. When Phillips approached, Drega got out with a rifle and fired at him. Although Phillips was hit, he returned fire and tried to escape into a nearby field. Drega followed him into the field and killed him.

Moments later, another state trooper, Leslie Lord, arrived at the scene. Drega shot Lord from about 150 feet away before he could exit his car, killing him as well. Drega then stole Phillips' police car and drove to the Colebrook District Court. He approached Judge Vickie Bunnell, who had warned others to evacuate when she saw him with his rifle. Drega shot Bunnell in the back and killed her.

Dennis Joos, the editor of the local newspaper, tried to disarm Drega after he had shot Bunnell. During their struggle, Drega shot and killed Joos. After the shootings, Drega returned to his property, where he set his house on fire.

Drega then crossed into Bloomfield, Vermont, while driving the stolen police car. He fired at New Hampshire Fish & Game Warden Wayne Saunders, hitting him multiple times but not fatally. Saunders managed to retreat into the Connecticut River.

Eventually, Drega took a stand on a dead-end road on the Vermont side of the river. Law enforcement from various agencies surrounded him. Drega opened fire again, wounding several officers, including state troopers and a U.S. Border Patrol agent.

A gunfight ensued, and after the shooting stopped, agents tried to rescue the injured officers. When they approached in a vehicle, Drega opened fire once more. In the end, two officers, state trooper Charles West and Border Patrol agent Stephen Brooks, advanced toward Drega's position. As Drega aimed to shoot again, he was shot and killed by the officers, ending the violent confrontation.