Gunmen killed a state police officer and 10 members of his family, including five children, during a violent weekend that left at least a dozen Mexicans dead in separate events.
The shooting late Saturday also killed a street vendor in front of the house of state police officer Carlos Reyes, said Tabasco deputy prosecutor Alex Alvarez. Among the five children killed was a 2-year-old boy.
Reyes was a member of a special unit of high-level officers who investigated organized crime and kidnappings, the Latin American Herald Tribune reported.
Police hadn't determined a motive for the attack but Reyes directed a car chase and raids on two homes on Wednesday that led to the death of three suspected gang members and the arrest of seven others, Alvarez said.
"It is confirmed that [the assailants] wanted to kill the state police officer but they killed his whole family," Alvarez said.
At least a dozen gunmen in three SUVs sprayed the house with bullets, leaving police to find 11 bodies scattered inside three houses, the Latin American Herald Tribune reported.
An official from the Tabasco Attorney General's Office told the newspaper the killers "had no mercy" and were taken by complete surprise.
Meanwhile, seven people dining inside a new restaurant in Hostotipaquillo, western Mexico were also gunned down Saturday night.
Those attackers, armed with AK-47 and AR-15 assault rifles, arrived in four SUVs and opened fire, the Herald Tribune reported.
"The inauguration event at the Los Agaves restaurant had just ended. And only the owners and workers were still around when armed subjects arrived to carry out the attack," Hostotipaquillo police chief Lucio Rosales said,
Police there found 150 bullet casings outside the establishment, the Herald Tribune reported.
In Mexico City, authorities on Saturday found the decomposing bodies of two women in the trunk of a car that had been abandoned for at least a week, the Reforma newspaper reported.
A city investigator told the newspaper that the women had been decapitated and the heads left inside a cooler in the back seat of the car.
He said one of the women had been arrested in 1999 for the kidnapping of nine relatives of an alleged drug dealer.
More than 6,000 people died last year in a wave of drug-related violence.
The Associated Press contributed to this report.