Two men were fatally shot Sunday night in separate attacks in Southeast and Northeast Washington, continuing a surge of killings that has claimed nine lives in the District in the past week, including two brothers and a U.S. Capitol Police officer.

The 51 homicides recorded in the District this year represent a 34 percent spike from the same period in 2020. Last year ended with a 16-year high in killings.

Homicides, fueled largely by an increase in gun violence, are rising in the District for the fourth consecutive year.

“We had a very tough weekend,” Mayor Muriel E. Bowser (D) told reporters Monday. She said she would meet with police “on developing a deep dive on some of those incidents.”

Bowser mentioned a new program, Building Blocks DC, that is getting underway to focus city services on the 151 blocks, or 2 percent, of the District in which 40 percent of gun violence occurs.

A shooting that killed two people and injured three others in Congress Heights last week was on one of those blocks. Officials haven’t said if the other shootings in the past week also have been in those identified areas.

The idea behind the program is to provide counseling, “Violence Interrupters” and other efforts that attempt to stop disputes before they turn violent.

Bowser noted that other cities around the country are also experiencing more shootings. “We’re all concerned about increased levels of gun violence and homicides,” she said.

The Bowser administration recently hired Linda K. Harllee Harper for a new position — director of gun violence prevention — to help run the Building Blocks program and help coordinate how different agencies respond to crimes involving firearms.

And last week, acting D.C. police chief Robert J. Contee III appointed a new executive assistant chief who will serve as ­second-in-command of the department and make illegal firearms a main focus.

Ashan M. Benedict previously spent 23 years with the federal Bureau of Alcohol, Tobacco, Firearms and Explosives, most recently as the special agent in charge of the Washington field office. He has investigated drug trafficking organizations, armed robberies, armed carjackings, deadly violence, terrorist attacks and mass shootings.

The two Sunday night shootings occurred less than a half-hour apart.

In the first, a 33-year-old man was shot about 9:20 p.m. in the 1800 block of 24th Street NE, a residential street near the National Arboretum and one block from the 5th District police station on Bladensburg Road.

That victim was identified as Dontra Harris.

Harris’s stepbrother, Treb Raines, 27, said the shooting occurred in front of the victim’s ground-floor apartment at Parkway Plaza, while his girlfriend and two sons, an infant and a 2-year-old, were inside.

Raines said his stepbrother shouted through an open window for his family to duck just as the gunshots erupted. “They were by the window,” Raines said in a brief interview. “He saved their lives.”

Harris’s 79-year-old grandmother, Gloria Harris, who lives in Southeast Washington, said her grandson had worked with his grandfather at his landscaping company until the grandfather’s death three years ago. She said Dontra Harris had worked odd jobs since.

“He was a good kid, and he was doing the right things,” Gloria Harris said, adding, “He always came to help with anything I needed.”

Gloria Harris said that earlier Sunday, her grandson had confronted someone who made derogatory comments to his younger brother. That person followed her grandson home, she said. Police have not made any arrests or commented on a possible motive.

“I think he was targeted,” Gloria Harris said. “It’s crazy out here. You can’t even look at somebody different. Back in my day, you’d fight and be friends the next weekend. Now they got guns, and they shoot you.”

The other shooting Sunday occurred about 9:45 p.m. in the 4300 block of Wheeler Road SE, near Southern Avenue, in the Washington Highlands neighborhood.

Police identified the victim as Juwan McCrae, 22, of Southeast Washington. Efforts to reach relatives of McCrae and other victims were not successful.

Three men were killed Saturday. Julius Hayes, 37, was shot on the street in the Kingman Park neighborhood in Northeast Washington, and brothers Antuan Davis, 26, and Anthony Davis, 29, were shot inside an apartment in Washington Highlands in Southeast Washington.

On Friday, Capitol Police Officer William Evans was killed when a vehicle rammed him and another officer outside the U.S. Capitol complex. Police fatally shot the driver of the vehicle.

On Thursday, 18-year-old Michael Benbow was killed in a shooting that also injured two others, including a juvenile female, inside an apartment near Congress Heights in Southeast Washington.

And on Wednesday, police said, five people were shot at an apartment complex on Congress Street in Congress Heights. Keosha Ferguson, 28, and George Evans III, 25, were killed in that incident.

Michael Brice-Saddler contributed to this report.