Six people were killed in northern Mexico while taking part in a Holy Death ceremony on the Day of the Dead, when millions of Mexicans pay homage to their late friends and relatives, prosecutors said.

The incident occurred in the city of Torreon, Coahuila state, when several armed men burst into the ceremony at around 5:00 p.m. Friday.

Authorities with the state Attorney General's Office said the assailants opened fire with high-caliber weapons, leaving four men dead at the scene. Two others were seriously wounded and died later at a local hospital.

State police and army soldiers were on the scene as the investigation began.

The Holy Death cult, popular among drug traffickers and some other Mexican criminals, is a blend of Christianity, Indian traditions and folk beliefs that arose in the 1940s in poor Mexico City neighborhoods and subsequently spread throughout the country.

Condemned by the Vatican, the cult is not recognized as a religious denomination by the Mexican government.

The Holy Death cult, which claims to have 5 million members around the world, has its principal church in Mexico City.

In another violent incident Friday morning in the same city, four dismembered bodies were left outside a federal prosecutor's office by suspected organized criminals.

The body parts of two women and two men were found in plastic bags inside a vehicle, prosecutors said.

Authorities also found a threatening message whose content was not revealed.

Torreon has been controlled in recent years by the Los Zetas drug cartel, but a challenge leveled by the rival Sinaloa mob has led to numerous turf battles. EFE