Six people were killed over the weekend in the District during an unusual spate of violence at the start of the year.

The latest homicide occurred about 10:55 p.m. Sunday in the 800 block of Varnum Street NW, in Petworth. Police said James Lamont Stewart, 28, of Capitol Heights, Md., was shot and later died at a hospital. No other details were made public.

About three hours earlier, police said, Damon Dukes, 25, of Northwest Washington, was fatally shot in the 200 block of V Street NW.

In other incidents, two people were found dead in a burning home, and police said they had been killed; a man was stabbed in a domestic dispute; and another man was shot.

The killings brought the total in the city this year to seven. The violence came shortly after the District closed the book on a deadly 2018 in which police counted 160 homicide victims . That was nearly a 40 percent increase over 2016.

Law enforcement authorities have blamed the slayings over the past year on too many guns being used to settle disputes. They also said that the percentage of robbers and other assailants using guns has risen, even as violent crime has dropped since 2012.

“Our focus continues to be on how we deploy our officers and resources to focus on illegal guns,” Mayor Muriel E. Bowser (D) said at a news conference Monday to highlight initiatives for this year.

The mayor said she wants police to “focus on repeat violent offenders, work hand in hand with our federal partners so they are taking gun crime as seriously as we are and are protecting us against people who have demonstrated that they are willing to use guns in our community.”

Three of the weekend’s homicide victims were killed by gunfire. Early Sunday, a man was found in the unit block of O Street NW suffering from gunshot wounds, police said. As of Monday night, police had not identified the victim.

The violence started Saturday morning, when firefighters in Southeast Washington found the bodies of a man and a woman inside a small house burning on Ely Place. A spokeswoman from the D.C. Office of the Chief Medical Examiner said Monday that both victims had suffered blunt-force trauma to the head and had been asphyxiated.

They were identified as Joseph Burgess, 60, who owned the house, and Regina Bowman, 50, of Southeast. No arrest had been made as of late Monday. Burgess’s son recalled his father on Sunday as a man with a “loving heart” and said he had many years ago worked as a civilian employee for the D.C. police.

He had lived on Ely Place since 1987. The son, Joseph L. Burgess, said he did not know what could have led to the killings.

Police Chief Peter Newsham, speaking at a news conference on the mayor’s plans for the year, said detectives have “made some pretty good progress” in their investigation of the deaths on Ely Place. But, he said, “I would not say we have a suspect.”

The chief said there is evidence that the fire and another smaller fire in a house across an alley were both intentionally set.

In another incident, police went Sunday to the Garfield House, an apartment house in the 2800 block of Wisconsin Avenue near Washington National Cathedral.

Vongell Lugo, 36, was found in a hall with stab wounds, according to police, and was pronounced dead.

Police immediately arrested Collin J. Potter, 26, a Navy hospital corpsman based at Marine Corps Base Quantico in Virginia. A base spokesman confirmed Potter’s affiliation and said Potter had enlisted in the Navy in 2010.

Newsham declined to discuss details of the case but described it as being domestic in nature.

Lugo’s relatives could not be reached Monday. His LinkedIn page lists various jobs that include management positions at clothing stores in the D.C. area. His work at the time of his death could not be confirmed.

Antoinette Aguilar, 33, said she worked for Lugo when she joined the seasonal staff at Bloomingdale’s in Bethesda, Md., in 2010 and 2011. She described the manager as a “nice, outgoing person. I’m really sad to hear what happened.”

She said Lugo was always quick with a joke and made the shifts bearable through lighthearted humor. “He was easy to talk to,” Aguilar said Monday. “He got the job done.”

Fenit Nirappil, Martin Weil and Rachel Weiner contributed to this report.