Nine people were shot and wounded, including two juveniles, early on Wednesday in Washington, DC, police said.

Shortly before 1 am police responded to a report of a shooting on Meade Street in the northeastern quadrant of the US capital, Assistant Chief Leslie Parsons of the Metropolitan Police Department said in a statement on Twitter.

Upon their arrival officers discovered multiple shooting victims, including a 9-year-old and a 17-year-old, Parsons said.

A dark coloured SUV seen driving through the neighbourhood, stopped and then shot at the victims outside enjoying the July Fourth holiday, Parsons said, calling the shooting targeted.

Several victims were transported to local hospitals by DC Fire and EMS while others transported themselves.

All the victims suffered non-life threatening injuries, Parsons said. None have been identified.

It was not immediately clear if there was more than one shooter in the vehicle and no arrests have been made.

The DC shooting is the latest in a string of mass shootings over a violent holiday weekend.

Twenty-eight people were shot, two fatally at a block party in Baltimore early Sunday. Authorities say many of the shooting victims were under 18.

On Monday night, a gunman in a bulletproof vest has opened fire on the streets of Philadelphia, killing five people and wounding two boys, 2 and 13, before he surrendered to responding officers, police.

Three people were killed and eight others injured when several men fired indiscriminately into a crowd of hundreds that had gathered in a Texas neighbourhood following a festival in the area, authorities said.

The shooting in the Fort Worth neighbourhood of Como happened late Monday night, about two hours after the annual ComoFest ended.