MONTERREY: News anchors at the largest media company in the Spanish-speaking world, Mexico-headquartered Televisa, were last week presenting the 9pm evening TV news live when a convoy of gunmen drove by, threw a grenade at the studio and opened fire.

The news team, undaunted, continued to broadcast, reporting on the attack as it happened, while they called the police for help. There were no injuries, although one of the station's outer doors were riddled with bullets.

The attack in Monterrey, Mexico's second largest city and industrial capital was in every sense a warning salvo, and lest there be any misunderstanding, a handwritten note offered a suggestion for future coverage of the nation's massive drugs industry.

"Stop reporting just on us. Report on the narco's political leaders."

This was an apparent reference to the Mexican government, which is rife with corrupt politicians who protect the drug barons in return for payoffs.

Mexico is acknowledged as one of the world's riskiest nations in which to follow a journalistic career, with warring drug cartels attacking and sometimes killing crime reporters who try to unveil the truth about the drug trade. An estimated 5,700 people were killed in 2008 in drug-related violence in Mexico.

Data sourced from AdAge.com; additional content by WARC staff