Inside a restaurant near downtown Washington, in the small hours of a Sunday morning, one man drew a gun and shot and killed another. Other patrons followed the gunman outside, tackled him, grabbed his gun and tried to hold him for the police, authorities said.

A friend of the gunman’s tried to pull him away and threatened to shoot the patrons if they did not turn him loose, according to the U.S. Attorney’s Office for the District. Prosecutors praised the patrons, who they said held onto the gunman at the El Sauce restaurant, in a red-brick rowhouse in the 1200 block of 11th Street NW, near the Logan Circle neighborhood.

On Friday, Alexis Pineda, 26, of Suitland pleaded guilty in Superior Court to a charge of second-degree murder while armed in the killing of Jose Manuel Hernandez-Romero, 24, the prosecutor’s office said.

Prosecutors said Pineda’s friend, Jaime Cruz, 30, of Lanham pleaded guilty Oct. 4 to obstructing justice in the incident, which occurred about 2:30 a.m. on March 27, 2011.

In a statement, the prosecutor’s office said the victim was shot once in the chest “without provocation.”

According to charging documents, a witness told police that Pineda had stared at the victim, and then asked him in Spanish, “What’s up?” The witness said the victim did not respond and Pineda pulled a gun from his waistband and fired.

At an earlier hearing, a prosecutor said a deportation order had been issued for Pineda, a native of Guatemala, after he was discovered in Arizona in 2007.