Five people were killed in a clash with army soldiers and state police on a highway in the northwestern Mexican state of Sinaloa, officials said.

According to reports, heavily armed individuals riding in several SUVs had set up a checkpoint on the highway and were sparking fear among motorists.

A convoy of army troops and state police was dispatched to the scene and met by gunfire, prompting a shootout that ended with an armored Chevrolet Suburban set ablaze and five people dead inside the vehicle.

Sinaloa state Attorney General Marco Antonio Higuera Gomez confirmed the number killed in the clash and said one of the lanes of Mexican Federal Highway 15 had to be temporarily blocked while firefighters put out the blaze.

Authorities also seized a Dodge Ram with weapons inside, including a .50-caliber Barrett rifle.

State police and army soldiers launched an operation in the area after the clash, stopping and searching vehicles in an attempt to track down the assailants who managed to flee.

Sinaloa is the birthplace of the first generation of high-profile Mexican drug traffickers, including Joaquin "El Chapo" (Shorty) Guzman, the fugitive boss of the Sinaloa cartel and - according to Forbes magazine - one of the world's richest people.

Though El Chapo's mob dominates the drug trade in the northwestern state, challengers have been trying to encroach on the Sinaloa cartel's territory.

Conflict among rival drug cartels and between the criminals and the security forces has claimed some 50,000 lives in Mexico since December 2006, when newly inaugurated President Felipe Calderon militarized the struggle against the traffickers.