- The navy says it will need to carry out more tests to make a final determination
- Lazca is the subject of a $5 million reward from the State Department
- His death will be a blow to the Zetas but not its death knell
- He earned the nickname "The Executioner"
(CNN) -- The head of Mexico's notorious drug cartel, Los Zetas, is believed to have been killed in a gun battle with the Mexican Navy, authorities said Monday.
The Mexican Navy said strong evidence points to Heriberto Lazcano Lazcano as one of two men killed in a shootout Sunday in the northern state of Coahuila.
But, the navy added, it will need to carry out more forensic tests to make a final determination.
Lazcano, who is the subject of a $5 million reward from the U.S. State Department and another $2.3 from Mexican authorities, has been rumored killed or captured several times in the past.
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A boost to Mexico's oil future? If indeed he is dead this time, it will be a blow to the cartel, but would not necessarily mean its demise. The Zetas is not centralized as some other cartels, such as La Familia, analysts say.
Lazcano, 37, served in the Mexican armed forces as part of its elite Airborne Special Forces Group, dedicated to battling drug cartels.
But in the 1990s, he and several other Special Forces members were recruited by the Gulf cartel to create its enforcement, Los Zetas.
In the ensuing years, the Zetas split into its own major drug trafficking organization and have waged a bloody turf war with its former employers.
The violence has left thousands of civilians dead. For his role, Lazcano earned the nickname "The Executioner."
The shootout Sunday occurred when Mexican Navy vehicles on patrol were attacked by assailants from a moving vehicle using grenades and firearms. One naval service member received non-life threatening injuries in the engagement, the Navy said.
Two attackers were killed. And authorities are hoping that Lazcano, who earned the nickname "The Executioner," is one of them.
Lonzo Cook, Nelson Quinones, Victor Badilla in Coahilla state
