Mexico captures Zetas drug lord Ivan Velazquez Caballero
Mexican security forces say they have arrested one of the country's most wanted drugs traffickers.
Ivan Velazquez Caballero, known both as El Taliban and as Z-50, was a commander of the notorious Zetas cartel.
Police paraded their prisoner - who was arrested by marines in the city of San Luis Potosi - on national TV.
The arrest comes days after it was reported that Velazquez had split from the Zetas and joined the rival Gulf Cartel.
He is believed to have controlled some of the most important drug routes into the United States and ruled them with cold brutality.
For the outgoing administration of President Felipe Calderon, the capture of Ivan Velazquez, alias "El Taliban, is a significant scalp.
Infighting within such a large and multi-faceted organisation like the Zetas is to be expected, analysts say, with so many competing groups jostling for overall control.
While the government may point to the arrest as an example that its military strategy against the drug cartels has worked, critics say the Zetas were allowed to become too powerful under the current administration.
The incoming administration, of President-elect Enrique Pena Nieto, say their approach to the drugs war will be different.
But they face a daunting task in trying to bring the now-warring factions of the Zetas under control.
He had a reward of 30m pesos ($2.3m, £1.5m) on his head.
Masked Mexican marines displayed the handcuffed suspect alongside two alleged accomplices and an array of weapons and other contraband - including drugs - seized during the arrest.
Police say Velazquez, 42, was the Zetas' main leader in the states of Zacatecas, Nuevo Leon and San Luis Potosi.
He is said to have been at war with another leader of the gang, Miguel Angel Trevino, known as Z-40, a former member of the Gulf Cartel.In-fighting
Police believe a recent surge in mass killings was due to a split within the Zetas.
In August, a man survived a mass shooting near the city of San Luis Potosi by playing dead.
He let the attackers - from his own cartel, the Zetas - pile him into a van alongside the bodies 14 others who had been shot dead.
As a result of the survivor's account, it became clear that the Zetas had split into two factions.
One faction is said to be led by one of the founders of Los Zetas, Heriberto Lazcano alias "El Lazca" or "Z-3"; the other is led by Miguel Angel Trevino.
More recently, notices have been displayed saying Ivan Velazquez had joined forces with the Gulf Cartel.
The Zetas were enforcers for the Gulf Cartel in the 1990s.
By 2005, they had broken away and started to run criminal enterprises themselves, and now control whole swathes of north-eastern Mexico.
On Monday, 35 police officers were arrested in operations in the states of San Luis Potosi and Veracruz, accused of having links to the Zetas.