One of Mexico's most wanted men has been killed in a gun battle with police, officials say.
Luis Humberto Peralta Hernandez, 44, was a top figure in the Juarez cartel, which controls many of the drug smuggling routes from Mexico into the US, prosecutors said.
Also known as The Condor, he is accused of involvement in almost 100 murders.
He was killed in the northern city of Chihuahua on Tuesday, but officials only made his death public on Thursday.
Mr Peralta Hernandez had been carrying a false ID, which had delayed his identification, said the Chihuahua state prosecutors' office.
They also said that he had worked for the state prosecutors' office for nine years, during which time he is believed to have carried out most of the murders of which he was accused.
He was shot dead by federal police in a busy Chihuahua street. Three of his alleged accomplices were arrested and have been taken to the capital, Mexico City, for questioning.
Police say the Juarez cartel, also known as the Carrillo Fuentes Organisation, is behind many of the recent gruesome executions and decapitations in the border town of Ciudad Juarez.
The city saw more than 3,000 murders in 2010, making it by far Mexico's deadliest town.
Police blame a deadly battle between the Juarez cartel and its rivals from the Sinaloa cartel for much of the drug-related violence in Chihuahua state.
Last week, President Felipe Calderon announced that four additional battalions would be deployed to the north-east of the country to try to stem the violence.
Mexico has seen more than 34,000 drug-related killings since he launched his crackdown on the drug cartels in late 2006.