MEXICO CITY – Four police were killed and a fifth officer wounded early Tuesday in a shooting in the central Mexican city of Puebla, authorities said.

Before dawn, the officers went to an intersection on the city’s west side after receiving a call about a suspicious vehicle, the Puebla state Attorney General’s Office said.

The police stopped the car and were conducting a routine check of the passengers when another vehicle pulled up and several people jumped out and opened fire on the cops at point-blank range to “rescue” the occupants of the first vehicle, the AG office said.

The dead were identified as three Puebla municipal police and one officer from the suburb of San Andres Cholula, while the wounded officer is listed in serious but stable condition at a hospital in the city.

The attackers were armed with AR-15 and AK-47 assault rifles, weapons of choice for Mexico’s powerful drug cartels.

Puebla state has largely been spared by the drug-related violence that has claimed 15,000 lives in Mexico since December 2006, when newly inaugurated President Felipe Calderon launched a major offensive aimed at crushing the cartels.

On Monday, authorities in the western state of Nayarit announced the arrest of four reputed drug dealers in connection with the filmed beating and abuse of five teenage boys.

The video, which was posted on the Internet, depicts the beatings and shows the boys kissing each other on the orders of tormentors armed with assault rifles.

While the assailants can’t be seen, their remarks indicate they were out to teach the adolescents a lesson after they caught them trying to rob a house.

Nayarit’s attorney general, Hector Bejar Fonseca, said that police “studied the videos to detect, determine and identify the voices of the people who appeared there and the place where the events took place.”

He said that though the victims don’t want to press charges, authorities plan to prosecute the attackers for several offenses, including impersonation of a police officer.

Police made the arrests after an anonymous tipster called to say that some men were in a bar boasting that they were the ones behind the video, the attorney general said.

Officers went to the bar and took four men into custody, but a fifth suspect managed to get away. EFE