Mexican authorities are investigating a gruesome discovery south of the border in south of the border in San Fernando.
Officials reported finding 72 bodies in a ranch about 13.7 miles northeast of the rural Tamaulipas city.
The Mexican Navy reported on Wednesday that a man arrived at a highway checkpoint bleeding from a gunshot wound and asking for help.
The man reported being injured on a nearby ranch prompting Navy officials to send out patrols and an aerial unit.
Officials reported that the aerial unit spotted the suspects fleeing in several vehicles.
Authorities arrived at the ranch sparking a series of shootouts and ending with the deaths of one Naval Marine and three gunmen.
Officials reported the arrest of a juvenile male at the scene.
Authorities also seized 21 assault rifles, thousands of rounds of ammunition, bulletproof vests, army uniforms and other items.
Based on information from the injured man, authorities were able to find the bodies of 58 men and 14 women.
Identities for the bodies were not immediately available.
The Associated Press reported that the the 72 bodies might be those of Central and South American immigrants who were kidnapped and held for ransom.
Central and South American Immigrants are commonly held for ransom by Mexican criminal organizations.
A federal official told The Associated Press that the man who escaped from the ranch was an immigrant and that the other may have been killed because they didn't or couldn't pay fees or ransoms.
The official told the The Assoicated Press that investigators believe the 58 men and 14 women may have been killed recently.
The case remains under investigation by federal authorities.