People stand in front of a partially burned vehicle after gunmen shot and killed an as of yet undetermined number of people in the Tepito neighborhood in Mexico City, Thursday June 6, 2013. (AP Photo)
MEXICO CITY (AP) — Two gunmen stormed into a gym and killed four people in a tough Mexico City neighborhood that is home to the area's biggest black market, authorities said Thursday.
Mexico City Mayor Miguel Angel Mancera said three men who were exercising were killed at the scene and the fourth man, identified as the gym owner, died later in the hospital.
The shooting happened in the Body Extreme gym in Tepito, one of Mexico City's most dangerous neighborhoods.
Mancera said the gunfire appeared to be targeted at the first three men, and the business owner was shot after confronting the armed men. Agents found six bullet shells inside the building.
"It was a direct attack. There were about 30 people at this place," he said.
Police later detained two people who were armed and in the same neighborhood. They opened fire on police, without hitting them.
Josefina Ramirez said her nephew was one of the four killed, along with two friends and an instructor.
"Two masked men came and just started shooting," she said. "He had no enemies."
Tepito is the main clearinghouse for millions of dollars of contraband, from guns and drugs to counterfeit handbags that come through Mexico City.
A dozen people from the neighborhood were kidnapped nearly two weeks ago from an after-hours bar in the city center. Three people have been detained in the kidnapping, but there is still no sign of the 12 who were taken in broad daylight May 26 by heavily armed and masked men.
It was not immediately clear if the shooting Thursday had anything to do with the kidnapping. The mayor said he did not want to speculate on whether the two attacks were related.
The disappearance of the 12 has been linked to a murder May 24 outside another Mexico City bar, according one public security official who was not authorized to speak on the record. Both crimes may have had to do with a dispute over street drug sales, the official said, something that organized crime groups in Tepito have controlled for decades.
The shooting Thursday so close to the two other crimes raised fears that an organized crime battle could be breaking out in Mexico's capital, which has been mostly spared from the cartel wars that have caused so much violence along the U.S.-Mexico border and in other parts of the country.
"We are going after those who carried out these attacks, those who have sought to cause unrest in Tepito," Mancera said.
The shooting brought an enormous police operation, including helicopters flying over the mostly residential street.
One woman crying at the scene said her boyfriend was killed, but wouldn't give her name, only claiming his innocence and shouting "you know who did this."
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