Investigators obtained DNA from the remains of the parents of Los Zetas cartel boss Heriberto Lazcano Lazcano as part of an effort to confirm that the drug trafficker was killed in a shootout with the security forces earlier this month.

Lazcano, founder and leader of a drug cartel known for its cruelty, died in an Oct. 7 gunfight with marines in the northern state of Coahuila.