Eight people died and five were injured in a shooting at a busy nightclub in the town of Jerez, in northern Mexico, police said Sunday.

The incident in Zacatecas state took place late Friday into Saturday when heavily armed men, arriving at the bar in two vehicles, burst in and began shooting indiscriminately, a report from the Security Secretariat said. 

Six people died on the spot and two more succumbed while receiving medical attention; five people remained hospitalized on Sunday for gunshot wounds.

Victims included club employees, musicians and customers, local media said. Witnesses said people panicked as the club's floor became awash in blood.

The bar, called "El Venadito," is in the center of Jerez, a municipality about 60 kilometers (36 miles) southwest of the state capital city of Zacatecas.

Jerez has been hit in recent years by a wave of violence that last year forced hundreds of residents of nearby rural communities to leave their homes.

Zacatecas state is a strategic point for the US-bound drug trade, which has sparked violent disputes between the Jalisco New Generation and Sinaloa cartels, Mexico's most powerful.