Mexican authorities said that Lazcano was killed on Sunday afternoon during a gunfight on a baseball field in Progreso, a town in Coahuila state 80 miles from the Texas border.
According to the Navy, a convoy of Marines was responding to reports of armed men when it came under attack. Men in a moving vehicle threw grenades at the Marines. The Marines returned fire, killing two suspects.
Officials later identified one of the bodies as Lazcano. Authorities say they found guns, ammunition, grenades, and a rocket launcher inside the vehicle.
The U.S. had offered $5 million for Lazcano's head, while the Mexican government had offered a $2.3 million reward of its own.
On Saturday, Mexicans Marines captured another Zetas leader named the Squirrel, who helped run the organization in three Mexican states bordering Texas. Officials have linked Salvador Alfonso Martinez Escobedo to more than 200 deaths, including the murder of American jet skier David Hartley on a border lake in 2010, was arrested in Nuevo Laredo along with several other alleged Zetas soldiers.