The shooting occurred in the Como section of Fort Worth in Texas, hours after the end of the neighbourhood's annual ComoFest.

340 mass shootings have taken place across the country so far this year.

Authorities offered no motive for the gun violence, which erupted in a courtyard of grass and pavement between a pair of two-story rowhouse structures in South Baltimore's Brooklyn Homes community.

The five-year-old who shot the baby boy was able to gain access to a handgun in the apartment, reports show.

Jake Davison, who shot dead five people, killed himself after the six-minute shooting spree.

Across the US there has been a rise in gun deaths, including nearly 200 over the holiday weekend.

Biden calls shootings in the US an 'international embarrassment'.