Mexico's Navy reports that three marines and a naval cadet have gone missing, and authorities suspect that the Zetas gang is responsible.
The three marines disappeared on August 1 from the port city of Veracruz, while the cadet was reported missing a week later, according to a statement from the navy.
According to Rear Admiral Jose Luis Vergara, officials suspect the Zetas drug gang is behind the disappearances. Veracruz, on Mexico's Gulf coast, is a stronghold of the group.
This latest incident brings the number sailors who have gone missing in the region in the last two months to six. In light of these events, the navy has issued safety recommendations for navy personal and their families in the state of Veracruz.
Mexico's Navy has taken on a greater role in the fight against organized crime under President Felipe Calderon.