A hot air balloon smashed into a crowd in Missouri, knocking several bystanders to the ground.

At least two people were injured after the balloon rapidly lost altitude and its basket was dragged through the crowd in the town of Hannibal on Sunday.

Footage showed people screaming “oh my God!” as the aircraft hit a tree then slammed into the ground.

A woman and a child can be seen being knocked to the ground as the basket is dragged through the crowd.

The craft eventually regains altitude and flies away from the crowd.

The organisers of the Hannibal Bicentennial Celebration told Fox News on Sunday a young girl was knocked down, but there were “no serious injuries”.

A bystander told KHQA his mother was knocked down by the balloon’s basket and cut her hand.