Six people were killed and more than 20 injured in two shootings in Philadelphia and Chattanooga, Tennessee, the latest in a series of shootings that left members of Congress on alert to confront this crisis.

Several gunmen opened fire on busy South Street in Philadelphia, an area with many bars and restaurants, around midnight yesterday.

Officials said two men and a woman were killed.

In a separate incident in Tennessee, the police announced that at least 3 people were killed and more than 10 were injured in a shooting, which was followed by cars running over pedestrians as they fled the scene.

Celeste Murphy, the police chief of Chattanooga, Tennessee, confirmed to reporters that 14 people were shot, and three were hit by cars trying to flee the scene.

She added, "3 deaths have been confirmed, two related to gunshot wounds, and one resulting from injuries related to a car crash," noting that many of the injured are in critical condition.

The two incidents followed several shootings, including one that killed 10 people at a grocery store in Buffalo, New York, and another that killed 21 people at an elementary school in Yuvaldi, Texas.

Four people died at a medical center in Tulsa, Oklahoma.

Safety advocates are calling on the US government to take stronger measures to reduce gun violence, as the United States suffers from widespread mass shootings.

Democratic Senator Chris Murphy has been working with a bipartisan group of senators on reform measures that Republicans routinely reject.

Murphy said Sunday that the group hopes to craft a legislative package that attracts at least 10 Republican votes, in addition to the support expected from nearly every Democrat.

Last week, US President Joe Biden called for the passage of legislation to control firearms, in response to the recent violence, denouncing the transformation of "places frequented by people daily in America into killing and battlefields."

Republicans have succeeded in blocking most efforts to control gun ownership, although some have reported some recent change.

A poll published Sunday showed that 62 percent of Americans support a nationwide ban on semi-automatic rifles, and 81 percent support requiring a higher background check for all gun buyers.

Mass shootings in the United States of America have killed 18,574 people so far in 2022, including 10,300 suicides, according to Gun Violence Archives, which monitors shootings across the country.