Police in Mexico have arrested the father-in-law of the country's most wanted man, the drug boss Joaquin 'El Chapo' Guzman.

BBC: Mexico arrests Joaquin 'El Chapo' Guzman's father-in-law

But Jack Riley says that Guzman, whose nickname El Chapo means "shorty" in Spanish, is more ruthless than the legendary gangster.

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It is estimated that El Chapo controls at least 60, 000 square km (23, 000 square miles) of rugged mountains in Sinaloa and Durango.

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El Chapo is now believed to be 55 to 59 years old.

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Joaquin Guzman, known as "El Chapo", or "Shorty", was arrested in 1993.

BBC: Shorty Guzman's 'security chief' arrested in Mexico

Armchair warriors wondered if El Chapo had set up his old friend Nacho, out of concern that his Jalisco kingdom was becoming too independently powerful.

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In 1993, El Chapo was arrested in Gautemala and extradited to Mexico, where he was indicted and jailed on drug charges and murder.

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