Mexico City ( CNN ) -- Investigators exhumed the mother of one of Mexico 's most notorious cartel kingpins Monday , two weeks after thieves apparently made off with her son 's body before authorities could conclusively confirm his identity . Now they plan to do DNA tests to verify that the man they killed in a gunbattle earlier this month was Heriberto Lazcano Lazcano , leader of the Zetas drug cartel , Mexico 's attorney general 's office said . Masked federal police Monday guarded the cemetery in central Mexico that houses the mausoleum containing the remains of Lazcano 's mother , Mexico 's state-run Notimex news agency reported . Photos : Mexico drug war desperation . It was the latest chapter in a dramatic saga that has cast a cloud of mystery over what could be one of the biggest accomplishments of outgoing President Felipe Calderon 's crackdown on cartels . Mexican authorities have said they have no doubt they killed Lazcano , thanks to fingerprints and photograph evidence . But additional tests will allow them to reach 100 % legal certainty , prosecutors said . `` Taking tissue samples ( from a direct family member ) is necessary to complete laboratory studies of the genetic fingerprint , according to the most modern and advanced protocols for identifying people , '' the office said . On October 8 , authorities proudly trumpeted the death of Lazcano , who was known as `` El Lazca . '' The next day , they revealed they no longer had his body ; gunmen had stolen it from a funeral home . They also said that members of Mexico 's navy shot him dead without realizing that the man in the suspicious car they 'd chased outside a local baseball game on a Sunday afternoon was the head of the ruthless Zetas cartel . Mexican navy : Zetas leader captured . `` Two people were killed , but for us , they were just two more criminals . We had no clue that it was El Lazca , '' Vice Adm. Jose Luis Vergara , a spokesman for the navy , said in an interview with MVS Radio shortly after authorities announced the news . Vergara said investigators thought he was `` a criminal , not even a capo , most likely a hit man in the town or something like that . '' Officials said a fingerprint match after the autopsy confirmed he was the man Mexico 's president described as `` one of the most important and most dangerous '' people on the country 's list of most wanted criminals . The United States and Mexico combined had offered rewards of more than $ 7 million for information leading to his capture . Lazcano was a onetime special forces soldier who became a founding member of the Zetas , a group accused of some of the most violent atrocities that have come to define the drug war . Lazcano , 37 , joined the Mexican armed forces in 1991 and was part of its elite airborne special forces group , dedicated to battling drug cartels . Soon after , Lazcano and several other special forces members were recruited by the Gulf cartel to create its enforcement arm , the Zetas . Zetas ' founder sentenced to 35 years . After the partnership ended in 2010 , the Zetas split into a major drug trafficking organization and have since branched out into extortion , kidnapping and human smuggling . Analysts have said it is unclear what impact Lazano 's death will have on the Zetas . The cartel had been in the midst of a bloody turf war with its former employer , the Gulf cartel , and also with the Sinaloa cartel . The fight for access to lucrative smuggling routes in northern and central Mexico has left thousands of civilians dead . Mexican authorities : Suspect arrested in Falcon Lake killing . CNNMexico.com and CNN 's Catherine E. Shoichet and Mariano Castillo contributed to this report .
Investigators will conduct DNA tests to confirm the identity of the Zetas leader . Police search a cemetery in central Mexico as authorities recover his wife 's remains . Authorities have said there 's no evidence they killed Heriberto Lazcano Lazcano . The cartel chief 's body was recovered from a funeral home .