The Gwinnett County police department closed 23 homicide cases in 2019. But seven deaths remain under investigation, including a shooting that killed two brothers, the department said this week.

Here are the 2019 homicide investigations that remain open:

Jan. 29: Just after midnight, several guests at a Days Inn near Stone Mountain heard gunshots. Officers arrived to find Ronald Horton Jr. dead inside a second-floor room. He was 28. Detectives believe three suspects entered Horton's room, fired shots and ran from the area. Police dogs were unable to track the suspects. In August, investigators released surveillance video of the three suspects in hopes of generating more leads.

>> MORE: Police ID man killed at hotel

>> RELATED: Metro Atlanta's 2019 homicides that remain unsolved

Ronald Horton Jr.
icon to expand image

March 22: Brothers William Thurman, 17, and Billy Roy Thurman, 25, planned to pursue hip-hop music. They had only lived in Gwinnett County a few weeks, according to family members. The brothers were visiting relatives in a Peachtree Corners apartment complex when they were shot to death in the laundry room, police said. A cousin was also wounded. "They didn't just kill my brothers," a sister, Lisa Thurman, said after the shootings. "They are killing my family."

>> MORE: Brothers killed in laundry room mourned

May 3: Shortly after 5 a.m., a resident of Patterson Circle near Lawrenceville called police to report gunshots. The front door to Eddie Waters' townhouse was locked. But officers noticed gunshots through the door and shell casings on the ground. After forcing their way inside, officers found Waters dead at the bottom of the stairs. The 44-year-old had been shot. Investigators have not publicly identified any suspects in the case.

> MORE: Police ram door, find man fatally shot on the other side

July 20: Investigators initially believed Ray Neal had died from one of his medical conditions. When she was unable to reach him, Neal's sister drove to his Lawrenceville-area house. She found Neal dead in a bedroom. He was 61. Officers saw blood on the bed, on the walls of the bathroom and on a shower curtain. But an investigator with the county's Medical Examiner's office also thought Neal had died from natural causes. But a local funeral home noticed marks on his neck. An autopsy revealed Neal had been stabbed to death. The medical examiner employee later resigned.

> MORE: Investigator resigns after missing dead man's stab wounds

Ray Neal was found dead July 20 inside his home on Lexington Avenue near Lawrenceville. An investigator from the medical examiner’s office initially declared he had died of natural causes; police are now investigating it as a homicide. SPECIAL PHOTO
icon to expand image

> MORE: Gwinnett police seek two suspects in woman's death

Nov. 1: Officers were called to the Oakwood Vista Apartments, near Norcross, after a resident heard gunshots. There, they found the body of Roberto Pacheco, who had been shot inside his ground-floor unit. He was 21. Pacheco's sister, who lives in Mexico, later said she was on the phone with him when she heard a gunshot. Pacheco's roommate and cousin was arrested, but not charged in connection to the killing. Santiago Torres Pacheco, 17, was accused of manufacturing and trafficking drugs. He remained late Tuesday in the Gwinnett jail, where he was being held without bond.

> MORE: Roommate of slain Gwinnett man arrested on drug charge

In an odd twist of events, the victim?€™s family in Mexico said they were worried about their loved one after hearing a gunshot while they were on the phone with him early Thursday.

Anyone with information on any of these unsolved cases is asked to contact the Gwinnett police department at 770-513-5300. Tipsters can also submit information anonymously through Crime Stoppers Atlanta by calling 404-577-TIPS (8477) or through the organization's website, www.stopcrimeatlanta.com