Local news reports said the Saturday night shooting occurred at a Sweet 16 birthday party at a dance studio in Dadeville, northeast of the state capital Montgomery, with at least 20 people shot.

“Currently there have been four confirmed fatalities and multiple injuries,” the Alabama law enforcement agency said in a statement, without stating whether a suspect had been detained or identified.

WRBL reported that during a preliminary investigation, police and sheriff’s office investigators suspected that an altercation led to the shooting at a teen’s birthday party, at around 10.30pm local time Saturday.

The US, a country of around 330 million people, is awash with some 400 million guns, and deadly mass shootings are a regular occurrence.

Police late Saturday confirmed two people were killed and four others wounded in a shooting in Louisville, Kentucky, the same city were a gunman slaughtered five people at a bank last Monday.