|Police have blamed suspected drug members for the attack at the Castillo del Mar in Cancun [Reuters]
In a sign of the widening violence in Mexico, eight people have been killed in Cancun after suspected drug gang members threw bombs into a bar on the city's outskirts, according to the local attorney-general's office.
The attack in the Caribbean beach resort, in southeastern Mexico, took place early on Tuesday.
Six women and two men died in the fire at the Castillo del Mar, which is frequented by locals.
The bar - located in a low-income area far from the city's tourist zone - had reported two earlier attempts at extortion, apparently by the Zetas drug cartel.
Bar employees have told police that unidentified men tossed petrol bombs at the establishment.
The attorney-general of Quintana Roo state, Francisco Alor, said the cause of the blaze is still under investigation.
"According to unofficial information, which we have not corroborated, two vehicles pulled up ... both black, and apparently six armed men tossed Molotov cocktails," he told a local radio station.
He said experts were examining the wreckage of the bar.
The bar offered table-dances and other entertainment, and had a rough reputation. Alor said the bar had had problems in the past, but did not offer any details.
Businesses throughout Mexico are often squeezed for protection money by drug cartels, which sometimes set fire to those that refuse to pay.
Cancun has largely avoided the bloodshed in which more 28,000 people have died in drug-related violence since late 2006. However, drug cartels and immigrant traffickers operate in the area.
The attack in Cancun came as masked police paraded Edgar Valdez Villarreal - one of the country's biggest drug lords - in handcuffs before reporters in Mexico City.
Wearing a green polo shirt and jeans, the man nicknamed "La Barbie" for his fair complexion smiled as officials discussed his capture near the Mexican capital on Monday.
"This operation closes a chapter in drug trafficking in Mexico," Facundo Rosas, a senior federal police official, told local television on Tuesday.
Six other men were arrested with Villarreal and police found weapons, vehicles, cocaine and cellphones at a safe house guarded by cartel members.
The US administration declined to say whether it would push for Villarreal to be sent to face trial in US courts where he has been indicted for drug trafficking.
"The federal police plan is to first process him here in Mexico for alleged crimes ... and then there are the cases pending outside the country, especially the United States," Rosas said.
Yet the arrest is unlikely to end the bloodshed that presents a growing image problem for Mexico as it struggles out of recession and seeks to hold on to tourist revenues.
More than 28,000 people have died since Felipe Calderon, the Mexican president, launched his crackdown in late 2006. The violence shows no sign of stopping as gangs battle for control of smuggling routes.
Officials say Villarreal, as a leader of the Beltran Leyva cartel based in central Mexico, trafficked a tonne of cocaine each month and was responsible for "several dozen" murders.
He is believed to be behind beheadings of rivals, the torture and mutilation of victims and the slaughter of the family of a marine who took part in the killing of Arturo Beltran Leyva, his former boss, in December.
But Villarreal's operations were small compared to Mexico's top gangs - the Sinaloa, Gulf and Juarez cartels - that smuggle the majority of the 140 tonnes of cocaine the UN estimates that Mexico exports to the US every year.
Speaking to Al Jazeera on Tuesday, Colin Harding, a Latin America analyst, said: "Civilians are in the frontline most of the time.
"The civilian population is not being protected by the federal authorities and there no is evidence at all that the flow of drugs into the US, which the different cartels has been battling about, is diminished at all."