Police warned of further violence and revenge attacks after a fatal shooting between two rival biker gangs in a restaurant in Waco, Texas.
Members of biker gangs involved in the shooting were reported to be travelling to the city and police said they received threats from the gangs.
Police arrested and charged 170 people on Monday after nine people died and 18 wounded in a shootout between Bandidos and Cossacks motorcycle gangs on Sunday at a Twin Peaks Sports Bar and Grill restaurant in Waco.
Waco police said the underlying reason of the dispute appeared to be control over territory and membership in north Texas.
When the shooting began, 18 police officers stationed near the restaurant intervened and opened fire as a response to bikers’ shooting.
"Yesterday's events was bad guys on bad guys. When our officers arrived, those bad guys turned their guns on our officers," Waco Police Sergeant Patrick Swanton said on Monday.
It was not known how many - if any- of the dead or wounded were result of the police fire.
Arrested gang members were charged with engaging in organised crime for capital murder and McLennan County Justice of the Peace W.H. Peterson set bail at $1 million for each suspect.
Bandidos is one of the largest biker gangs in the country and “involved in transporting and distributing cocaine and marijuana and are involved in the production, transportation and distribution of methamphetamine,” according to Department of Justice.