DURHAM, N.C. — Nearly a month after four men were shot and killed at a Durham townhouse, police say the unsolved homicide case is still a top priority for investigators, who continue to follow up on leads and interview witnesses and possible suspects.

Juan Coleman, Jamel Holloway, Lennis Harris Jr. and Jon Skinner were killed execution-style inside 2222 Alpine Road on Nov. 19. Police believe the slayings were drug-related and not random.

Detectives have been particularly tight-lipped about the case, and this week, in an attempt to protect the investigation, police had a judge seal search warrants from the crime scene to prevent dozens of pieces of potential evidence collected from the townhouse from becoming public record.

Durham Police Chief Steve Chalmers said the move was necessary.

"We will try to safeguard that as much as possible because we don't want information getting out as to what we're looking at, right now," Chalmers said.

Chalmers is optimistic about an arrest and calls the case a very active investigation.

"(Detectives) have so many things going on in this case," Chalmers said. "A lot of information is coming in."

Some of that information has come from the two survivors -- one man who jumped out of a window and the other who was found on the front porch, shot in the face. Both are out of the hospital, recovering from the injuries and the trauma.

Chalmers said his officers were not just focused on an arrest, but also on the conviction since those responsible could face the death penalty if convicted.

Authorities said witnesses saw three men running from the townhouse in the Breckenridge subdivision after the shots were heard.

One man was described as a black male with a light complexion, standing 6 feet to 6 feet 2 inches tall and weighing 180 pounds. He was wearing dark jeans and a black and white jacket.

The second man was described as a stocky black male, standing 5 feet 10 inches tall and weighing 200 pounds. He was wearing a burgundy flight jacket and jeans.

The third man was described as a black male with a medium complexion, standing 5 feet 10 inches tall and weighing 170 pounds. He was wearing a black flight jacket and blue jeans.

Authorities are offering up to $13,000 for information leading to the arrests and convictions of those responsible for the homicides.

Investigators urge anyone with information about the case to contact the Durham Police Department at  (919) 560-4440, ext. 259 or Durham CrimeStoppers at (919) 683-1200.