Can a musical genre be considered so dangerous as to be banned from the radio? Yes, according to the authorities in some parts of Mexico who have forced radio stations to take action in an attempt to stamp out the culture of "narco corridos", which they accuse of glamorising drug trafficking and gangsterism.
by Chris Summers and Dominic Bailey
BBC News Online
Corridos, or ballads, have been a Mexican tradition - especially in the north of the country - for at least 100 years.
Los Tigres del Norte are the foremost exponents of the narco corrido
The songs, based on polkas and waltzes, feature lyrics backed by accordions and brass bands.
The Mexican Revolution, which lasted from 1910 to 1917, triggered hundreds of corridos about legendary figures such as Pancho Villa and Emiliano Zapata.
But over the past 30 years the biggest growth area has been the narco corridos, which are based on the real lives of drug smugglers.
Among those heavily featured are the Arellano-Felix brothers, who ran a drugs cartel in the border city of Tijuana, and their arch-rival Amado Carrillo Fuentes, aka Lord Of The Skies, who was based in another frontier town, Ciudad Juarez.
Efforts to ban narco corridos
Mar 2001: The Mexican state of Sinaloa announces a "voluntary" ban on the broadcast of narco corridos
Jan 2002: Congress in the state of Chihuahua passes a bill "inviting" radio stations to ban narco corridos
May 2002: Government says it cannot enforce a national ban on narco corridos because of right to freedom of speech
Jul 2002: The state of Baja California Norte signs a "voluntary" ban agreement with radio stations
Oct 2002: The state of Nuevo Leon bans narco corridos
Elijah Wald, a former blues guitarist who has written a book on narco corridos, told BBC News Online: "The first thing a drug runner would do after a successful run was to hire someone to write a corrido about it."
Corrido performers normally charge thousands of dollars, or tens of thousands of pesos, to write and perform such a piece.
Mr Wald said: "I spoke to one corrido writer who wanted to be smuggled into the US. The smuggler would normally charge $1,500 but he did it for free provided the writer wrote a corrido about it."
Also popular are immigration corridos, such as Tres Veces Mojado (Three Times A Wetback) which was also made into a movie.
Jessie Morales' image is popular with gang members in LA
Mr Wald said most narco corrido writers and performers would deny writing bespoke songs for the drug barons.
"I asked one of the most well known, Reynaldo Martinez, if he wrote corridos for hire. He said 'No, but sometimes someone who likes one of my songs might give me a Land Rover.'
Mr Wald said: "Los Tigres del Norte are the kings of the kings and I would be surprised if they had ever taken any money."
Corridos, and narco corridos, were now "ubiquitous" in Mexico and had spread to California, Texas, Florida and other places with large Hispanic populations, according to Mr Wald.
They have also become popular in Colombia and in other parts of central America, such as El Salvador.
In the US the market for Mexican regional music, including narco corridos, is worth about $300m a year, with Los Angeles being the hub of the narco corrido industry. Los Tigres' most recent album sold nearly 500,000 copies in the US alone.
Two of the newest stars, Lupillo Rivera and Jessie Morales, sport the shaven heads and jewellery fashionable with Hispanic gang members in East LA.
While gangsta rap has Tupac Shakur, narco corrido has Rosalino "Chalino" Sanchez, who was murdered in Culiacan, the capital of the chaotic state of Sinaloa in May 1992. He had earlier been involved in a shoot-out with a gunman at a gig.
Mariluz Gonzalez, a spokeswoman for LA-based Fonovisa Records, which represents Los Tigres and several other narco corrido stars, said: "They are not glamorising the drug dealers' lives, they are simply telling a story. They are not promoting it."
But the Mexican authorities, appalled at what they see as the glamorising of drug smugglers and gangsters, have sought to ban the genre. The Federal Communications Commission has also taken action against several Spanish-language radio stations in the US.
Grupo Exterminador's songs tend to parody narco corrido
The Mexican Senate, unable to act itself because of freedom of speech legislation, exhorted individual states to restrict narco corridos, saying the songs "create a virtual justification for drug traffickers".
Since 2001 several Mexican states have negotiated "voluntary" bans with local radio stations in an attempt to keep narco corridos off the airwaves.
Mario Enrique Mayans Concha, president of the Baja California branch of Mexico's Chamber of Radio and Television Industry, said: "Narco-ballads set a bad example for the younger generation."
Antonio Mejias-Rentas, entertainment editor with the Los Angeles-based La Opinion newspaper, said: "There is a mixed feeling about them in the Mexican community; while there is an appreciation for the art form, there is also concern about the glorification of violence and drug consumption, much like in the gangsta rap world."
He said Los Tigres were generally well-regarded, adding: "Some of their narco-themed songs are regarded as classics, but lately they are better known for songs about immigration and other social concerns."
Fonovisa's Mariluz Gonzalez said: "Corridos are a tradition that has been going since the Mexican Revolution.
"They are a way of telling the people what is going on. It might be the truth or it could be twisted, you can't really tell."
La Banda Del Carro Rojo (The Red Car Gang) was a popular earlier narco corrido
She admitted: "There are some groups who have taken money and glorified these narcos."
But she said the Mexican authorities had often taken action as a way of muffling criticism.
"The Tigres put out a song earlier this year called Las Mujeres del Juarez which was about the murders of women in Ciudad Juarez, which is a very controversial subject, and the local government did not like it."
Despite being banned from the airwaves on both sides of the border narco corrido artists continue to sell well, Ms Gonzalez said.