Image caption Sergio Vega's lyrics often featured the drugs trade

Mexican singer Sergio Vega has been shot dead only hours after he had denied reports he had been murdered.

The 40-year-old singer, known as El Shaka, told a website he had increased security measures after a number of Mexican musicians were killed.

Musicians performing narcocorridos, songs celebrating the lives of drug barons, often become the targets of rival drug gangs.

Gunmen opened fire on Mr Vega on his way to a concert in Sinaloa state.

Mexican media reported Mr Vega was driving his red Cadillac on Saturday night when a truck started following him.

Shortly afterwards, shots were fired at the car, injuring Mr Vega and making him lose control of the vehicle and crashing it, his passenger told El Debate newspaper.

Deadly rumours

The gunmen then "finished Mr Vega off" with shots to the head and chest, El Debate reported the passenger as saying.

SERGIO VEGA, EL SHAKA Born 12 September 1969 in Sonora, Mexico

Emigrates to the US

Founds the band Los Hermanos Vega with his brothers

Band returns to Mexico under new name Los Reyes del Norte

Killed on 26 June 2010

Police confirmed they found spent bullet shells next to the driver's door.

The BBC's Julian Miglierini in Mexico City said rumours had been circulating among fans of the Grupero genre of music that Mr Vega had been killed.

Only hours before the shooting, he told the entertainment website La Oreja that reports of his murder had been mistaken.

"It's happened to me for years now, someone tells a radio station or a newspaper I've been killed, or suffered an accident," Mr Vega said.

"And then I have to call my dear mum, who has heart trouble, to reassure her," he explained.

He told the site that musicians performing Grupero music were worried, but that he had entrusted himself to God.

Mr Vega said he had increased his security measures after the killing in 2007 of Sergio Gomez, the singer of Grupero band K-Paz de la Sierra.

NARCOCORRIDO EL SHAKA I'm going to ask you a favour... Shaka told his people... I want to have some coca paste processed... Because that's what the customer wants... At the end if it rains and I get wet... You will get wet as well Translated extract from El Shaka

Mr Gomez was kidnapped after a concert in Michoacan, at which Mr Vega had also performed. He was found strangled days later.

At least seven Grupero musicians have been killed over the past three years.

Police have blamed drug gangs for the killings.

They say musicians who celebrate the lives of drug barons in their lyrics often become targets for rival drug gangs.