At least one man was fatally shot and eight other people were injured Sunday afternoon when three heavily armed men opened fire on a busy street in the Columbia Heights area of Northwest Washington, police said.

The man died at a hospital after the shooting, which police said happened just before 5 p.m. at 14th Street NW and Spring Road, a busy block in a vibrant neighborhood of stores, restaurants and housing.

Police Chief Peter Newsham said police were searching for three men after what appears to have been a targeted attack. Two of the men were armed with long guns, and one with a pistol, Newsham said.

“This type of brazen daylight activity in a very, very busy block I’m sure is scary for this community,” said Newsham, who was joined by D.C. Mayor Muriel E. Bowser at the scene. “I don’t know what people are thinking.”

Newsham said the men “opened up on a group that was in the block.” He said the victims were all adults, including eight men and one woman. In addition to the man who was slain, two victims were in serious condition and the others have injuries that are not believed to be life-threatening, he said.

The victims ranged in age from 18 to 62, according to a city official.

Newsham said the incident appeared to stem from a “crew dispute.”

“We’re familiar with some of the players,” he said.

Bowser (D) called the shooting “shocking.”

“Everybody should be outraged” that an attack could take place in a commercial area in the day, Bowser said.

The shooting is the latest in a violent month in the District, where at least 23 people have been killed since July 1. Before Sunday’s shooting, there had been 103 homicides in the city this year, according to the D.C. police website. Newsham said about 90 percent of the deaths were due to gunfire.

Newsham attributed the District’s homicide rate to increasingly lethal guns capable of carrying large magazines, as well as attackers who have previous arrests involving guns. “We’ve got to hold gun offenders accountable,” he said.

After Sunday’s shooting, police marked off 14th Street at Spring Road for a couple of blocks with crime tape. Dozens of yellow evidence markers were scattered along the sidewalk. A bicycle was discarded on the sidewalk, and a plastic chair was toppled over.

Along the block near the shooting are a convenience store, two restaurants and a clothing store.

Eduardo, who did not want to give his last name, citing safety concerns, said he saw a man shooting with a handgun from where he was sitting outside a restaurant about a half-block away.

“I thought it was fireworks at first,” he said. “But it was extremely loud and people started running.”

The shooting stopped and the attackers left in a black car, he said. Eduardo ran inside the restaurant and tried to call 911, and within two minutes police arrived.

Melissa Williams said she and her boyfriend were in a car and about to stop at a light when they heard about seven loud pops. Her boyfriend threw the car into reverse, and she saw people running from the sounds.

Muhammad Shah, the manager of Pizza D’Oro at 14th and Spring, said he and his team were in the back of the building but had the door open because of the heat when they heard gunshots. After they came outside, Shah said, police began clearing the block.

A man who works across the street from the shooting scene said he was inside the business when he heard 16 to 20 gunshots.

“We all just hit the floor,” said the man, who declined to give his name because he did not want the business associated with the incident.

When the man came out, he saw people lying on the sidewalk and he called 911.

He said people typically congregate on the street and that was “definitely why so many people were hit.”

Clarence Williams contributed to this report.