Armed men rumbled into a gritty neighborhood of the Mexican capital Thursday and gunned down six men hanging around a convenience store, fueling fears that one of the world's largest cities is falling prey to the cartel-style violence that has long terrorized other parts of the country.
More than 50 people have been killed in the past week in five apparently unrelated massacres, including four shot Thursday near the border city of Ciudad Juarez. But the Mexico City shooting has raised alarm among residents about a drug war that has long seemed distant.
"Massacres have arrived" in Mexico City, El Universal newspaper declared. But Mexico City Attorney General Miguel Angel Mancera said he did not know if drug gangs were involved in the middle-of-the night shooting in Tepito, a working-class neighborhood just north of the colonial center.
Drug dealing is rampant in Tepito, but Mancera said there also have been problems with disputes among carjacking gangs.
Gunmen in a white SUV drove up just after midnight to a street of drab apartment buildings, corner grocery stores and auto repair shops, witnesses said. They jumped out of the car and gunned down six men in their 20s and 30s who had just gathered in front of a tiny convenience store. A seventh man was wounded.
People were still out on the streets when the shooting occurred. Drug dealing and robberies have been on the rise in the neighborhood but store owners still feel safe enough to keep their businesses open late. That in itself contrasts with border cities like Ciudad Juarez, where streets empty and many business close in the early afternoon for fear of drug-gang violence.
Several Tepito residents said they assumed the gunfire was fireworks for St. Judas Tadeo Day, commemorated with processions and street festivals across the city. As word spread, they slowly emerged from their apartments, shocked to find bodies face down in pools of blood.
"I've never seen anything so horrific happen. I go around at 2 or 3 in the morning and nothing has ever happened to me," said Guadalupe Ramirez, a 53-year-old grandmother walking past the site of the shooting. She said her 15-year-old grandchild had just returned from buying milk when the gunfire erupted.
The gunmen exchanged angry words with the young men before shooting, Mancera told the Televisa network. Bullet casings of two different calibers _ 9 mm and .223 mm _ were found at the scene, Mancera said, suggesting there were at least two gunmen.
Police were interviewing relatives and witnesses to determine the background of the victims and a possible motive. At least two of the victims had criminal records for robbery, Mancera later told reporters without elaborating.
"We would like to reassure the population that we are going to find those responsible," Mancera said.
Neighbors said they didn't know if the six young men belonged to a criminal gang but that they routinely hung around on the street, drinking beer and using drugs.
"I'm thinking of never coming back because every day things get worse," said Juan Fernandez, 60, who travels more than an hour to Tepito to get to the only job he's been able to find _ as a clerk at the convenience store nearest to the shooting.
"You could come around at 11 or 12 at night and see how they come out, all these boys, drinking and smoking marijuana."
Carmen Vasquez, an unemployed 35-year-old, pulled her four children quickly past the shooting site on her way to a charity kitchen where she gets free meals every day.
"We walk with our children in fear. Because we never know where these criminals are going to come from," Vasquez said as her kids looked over their shoulders at candles that mourners had placed at the site. "I'm only coming here because I have to."
Trucks of Mexico City federal police circled the block periodically. By the afternoon the street was bustling again with people shopping and repairing cars, and giggling children playing pinball machines outside the convenience stores.
While crime is a major problem in Mexico City, cartel-style violence has been less common. Still, shootings between cartel gunmen and security forces have occasionally erupted during operations to arrest kingpins in the Mexico City area, one of the world's largest metropolises with an estimated 20 million people.
The epicenter of Mexico's long-running drug war is Ciudad Juarez, across the border from El Paso, Texas. More than 6,500 people have been killed in the city since a turf war erupted nearly three years ago between the Juarez and the Sinaloa cartels. Thousands more have died in many areas of Mexico as drug gangs have fought a government crackdown and each other.
Three women and a man were killed outside Ciudad Juarez and more than two dozen were wounded, many of them seriously, when armed men in several vehicles attacked buses carrying factory workers home early Thursday morning, said Arturo Sandoval, a spokesman for the Chihuahua state attorney general's office.
There were no known suspects or motive in the attack on a highway in the Valle de Juarez region, where a string of small towns have been under siege from drug gangs trying to control trafficking routes. Mayors and police chiefs have been killed in the area, and even churches have been attacked.
On Wednesday, gunmen killed 15 people at a car wash in Tepic, a city in the Pacific coast state of Nayarit. Over the weekend, gunmen massacred 14 young people at a birthday party in Ciudad Juarez, and 13 recovering addicts were killed in an attack on a drug rehab center in Tijuana.
Associated Press writer Olivia Torres in Ciudad Juarez contributed to this report.