Mexico says it has captured one of the country's most-wanted drug traffickers, Ivan Velazquez Caballero, known as "El Taliban".

Velazquez Caballero has been fighting a bloody internal battle with top leader of the hyper-violent Zetas cartel, Miguel Angel Trevino Morales, and officials have said the split was behind a recent surge in massacres and shootouts, particularly in northern Mexico.

"A person who is presumed to be, and acknowledges being, Ivan Velazquez Caballero, was captured in the state of San Luis Potosi" in north-central Mexico, the navy said in a statement.

Also known as "Z-50," Velazquez Caballero has a 30 million peso reward on his head.

If confirmed, Velazquez Caballero's arrest could calm some of the brutal violence that has hit border cities like Nuevo Laredo, across from Laredo, Texas, in recent weeks.

On September 14, eight men were found shot to dead and one hanging from a bridge in Nuevo Laredo, territory traditionally controlled by Trevino Morales, alias "Z-40." Analysts say 14 bullet-ridden bodies stuffed in a van in mid-August in San Luis Potosi were men loyal to "El Taliban," and may have been left there as a warning by Trevino Morales' underlings.

The Zetas cartel takes its name from a police radio code in which "Z" means "commander," and a number refers to rank.

If the man arrested as "El Taliban" is confirmed, the development could strengthen Morales, who shares leadership of the Zetas with Heriberto Lazcano, alias "El Lazca."

A US official played down recent speculation that Trevino Morales and Lazcano had also fallen out.

Lawmen and even competing drug capos picture Trevino as a brutal assassin who favours getting rid of foes by stuffing them into oil drums, dousing them with petrol and setting them on fire, a practice known as a "guiso," a Spanish word for "stew."

The Zetas are already considered the hemisphere's most violent criminal organisation. They have been blamed for a large share of the tens of thousands of deaths in Mexico's war on drugs, though other gangs also have repeatedly committed mass murder.