The controversial Mexican musical phenomenon known as the "Movimiento Alterado" arrives in San Diego on Thursday, with its explicit lyrics glorifying the violence and culture of drug traffickers.

Nearly two dozen singers, bands and norteño groups will headline a concert at the House of Blues, performing "narcocorridos," tunes that tell a drug lord's story.

This musical genre has been around for nearly two decades, first made famous by such groups as Los Tigres del Norte and Los Tucanes de Tijuana. However, the narcocorridos in the style that's come to be called the "Altered Movement" are more hard-core and explicit, analogous to gangsta rap in the United States.

"The lyrics are more violent," acknowledged José Ríos, a promoter in La Disco Music, the Los Angeles record label that features most of the artists in this style. "It's what people are requesting lately."

A wide range of leaders in Mexico, including politicians and law enforcement leaders, condemn these songs, saying that they promote drug trafficking and violence.

Ríos rejected that view, saying simply that these songs "tell things the way they are. These singers aren't inventing anything. The songs are a story of what's happening."

In "Mentes enfermas" ("Sick Minds", one of the most popular songs, El Komander refers to the war between the Sinaloa cartel and other criminal groups: "With bloodied hands we're armed and continue to kill enemies that challenge us, cleansing the territory, fighting battles, we never negotiate …. I'm very sick, I'm very blood-thirsty … I'm always sowing death."

Few Spanish-language radio stations heard in San Diego play this type of music, since most are licensed in Tijuana. In Mexico, stations are banned from airing songs that explicitly refer to drug trafficking.

"We play the traditional corridos, with their references to cowboys and lost loves," said Salvador Lujano, the DJ known as "El Chon" on La Invasora 99.7 FM. "We can't play corridos that talk about drugs or mention specific names."

Lujano said he's one of those people who believes narcocorridos, no matter how raw, do not breed trafficking or violence.

"Drugs, violence, have always existed," he said. "Just because I listen to a song I'm not going to turn into a trafficker or use drugs. Narcocorridos identify certain people; they don't lead you to become a drug dealer."

The DJ said that, if it was up to him, he would play songs from the "Altered Movement" in his morning radio show because "you can't go against the tide of what people like."

And the public that follows this music is very diverse, no just people who are involved in drugs, said Ríos, the promoter.

"Everyone has their musical taste and anyone can listen to the songs in this movement," he said. "There are lawyers, students, every type of person. There could be a thug that listens to these songs, but not all the people who listen are bad."

Judging by the Facebook followers of this music, most are young, men as well as women, who have learned to use the street slang common in Sinaloa state and the northern border.

It's worth noting that many of these Facebook posts are from locations where drug-related violence is greatest, such as Sinaloa, Monterrey and Chihuahua.

One of the Spanish-language posts in the page promoting the local concert says: "People, the Altered Movement is arriving in San Diego, California! Destroying everything, infecting the city of San Diego with the latest, most altered corridos!"

For Rَíos, being "altered" or "sick," is "something different, it's a lifestyle."

In fact, a glance at Facebook and Twitter posts, shows that many of this music's young followers

are adopting its language, using the products it promotes, including alcoholic beverages, and wearing clothes sold directly by the record label.

"It's all part of the movement," said Lujano. "All of their fans are using words that are very much in style."

Ríos expects 1,300 fans will attend Thursday night's concert, a sellout. A total of 25 artists are to perform, among them some of the most popular ones in this genre, such as El Komander, El RM and Los Buchones de Culiacán.

Singer Rogelio Martínez, who gained popularity last year in a dance contest on the Spanish-language TV network Univision, has joined the "Altered Movement," going by his initials, El RM.

He's left behind ranchera ballads to focus on narcocorridos, repeatedly explaining in interviews that "it's what the people want."

The concert tour includes dates across Mexico and the United States, with the latest show on March 17 in Las Vegas. The San Diego show is being heavily promoted through Facebook and Twitter.

Despite the drug-related violence pummeling certain areas of Mexico, Ríos said that when this concert is presented there, no extra security is needed.

"Thank God that we have never had a problem," he said. "These are regular concerts."

Det. Gary Hassen, the spokesman for the San Diego Police Department, would not say whether additional officers will be on hand at the House of Blues concert. He said "it's very likely" that his department knew about the show, "but we never release details of our operations before an event."

SanDiegoRed.com sent several e-mails to the spokesman for Live Nation, which operates House of Blues, seeking a comment about the concert but did not receive a response.

Though this music is very popular, Lujano, the DJ, said "it's starting to lose steam."

"Musical styles change constantly."

Pablo.sainz@sandiegored.com