At least two people died and 18 others were injured after a fight broke out between two groups on a street in US city of Tampa on Sunday.

The fight occurred at a time when hundreds of people were busy celebrating Halloween.

Two groups began fighting at about 3 a.m. as bars and clubs in the Ybor City neighbourhood began closing for the night, sending hundreds of Halloween partygoers into the street, Tampa Police Chief Lee Bercaw was quoted as saying by New York Post.

He said hundreds of innocent people were trapped during the shooting incident.

Video posted online shows people in Halloween costumes drinking and talking on the street when shots ring out, creating a stampede. Some people topple over metal tables and take cover behind them. Video from the aftermath shows police officers treating several people lying wounded on the ground, reports Fox News.

The circumstances which led to the fight are still not known.

One subject involved in the shooting has been detained by police for further questioning, police said in a statement.

Detectives are currently working to gather additional evidence and develop additional leads to determine what led to this shooting and identify all parties involved.

Local businesses have partnered with Tampa Police to review surveillance video that may have captured the incident.