Nine people have been killed and dozens injured after a brawl between rival biker gangs escalated into a shootout at a Texas diner.

At least 100 people were arrested after the incident at the Twin Peaks Sports Bar and Grill in the Central Texas Market Place, a busy shopping centre in Waco.

At around midday on Sunday, around 200 members of five biker gangs were organised a meeting over turf and recruitment.

The biker gangs began arguing in the restaurant bathrooms over a parking space, and heated words soon turned into a brawl that spread throughout the restaurants and outside.

The staff and diners at the restaurant locked themselves in the cold storage room for their own safety, as the bikers started attacking each other with knives and chains.

As the fight moved to the parking lot, as many as 100 rounds were reported to have been fired from around 30 guns.