|Cardenas Guillen, known as 'Tony Tormenta', was killed in a shootout with the military [AFP]
One of Mexico's most wanted drug dealers has been killed in a shootout with security forces, according to local media reports.
Antonio Ezequiel Cardenas Guillen, known as "Tony Tormenta" or Tony the Storm, was shot dead in Matamoros, Tamaulipas state, during a security operation in the northeastern border city.
Cardenas Guillen is believed to be a major drug trafficker for the Gulf Cartel.
Three other gunmen, two marines and a local newspaper reporter also died in the operation, which took place on Friday.
US authorities had indicted Cardenas Guillen on drug trafficking charges and offered a $5m reward for information leading to his arrest. Mexican authorities had also offered a $2m reward.
Cardenas Guillen's brother, Osiel, led the Gulf Cartel until 2003 when he was arrested by Mexican authorities.
Osiel was extradited to the US in 2007 and sentenced to 25 years in prison by a Texas court in February this year.
Franc Contreras, Al Jazeera's correspondent in the capital Mexico City, said that the death of Guillen was a major blow to the Gulf Cartel, but would probably not end violence in the region as the group was still fighting other cartels there.
Elsewhere in the country, police in Mexico City said that Harold "The Rabbit" Poveda, suspected of being the main cocaine supplier for Beltran Leyva drug cartel, had been arrested.
Meanwhile, family members have identified five bodies found in a mass grave near the Pacific coast town of Acapulco.
According to the families, the five belonged to a group of tourists who were kidnapped in late September while travelling to town.
Police discovered the mass grave containing a total of 18 bodies on Tuesday after an anonymous tip.
Contreras said that the state prosecutor said that the bodies had been buried for a month.
"Family members were able to positively identify these men and point out that at least five of them were in fact tourists.
"There was concern that maybe the men belonged to drug trafficking groups, but the families are saying no."
More than 28,000 people have been killed in escalating drugs related violence since Felipe Calderon, the president, began a crackdown on drugs trafficking in December 2006.