Gunmen stormed into a drug rehabilitation centre and opened fire leaving 24 dead and seven injured in broad daylight.
The bloody incident in central Mexico occurred at the unregistered drug centre on Wednesday when assailants began firing.
Three of the seven wounded are reported to be in serious condition after the shooting in the city of Irapuato, in the state of Guanajuato, according to The Guardian.
Currently Guanajuato is in the middle of a turf battle between the Jalisco cartel and a local gang.
The region in central Mexico has become one of the country’s hotspots of surging gang violence.
Rehab centres have previously been targeted by criminal gangs waging turf wars for control of the drug business.
Governor Diego Sinhué Rodríguez said: “I deeply regret and condemn the events in Irapuato this afternoon.
“The violence generated by organized crime not only takes the lives of the young, but it takes the peace from families in Guanajuato.”
Last month three unidentified assailants opened fire on the rehab centre in Irapuato, an industrial hub south of the state capital, the state government said in a statement of their initial investigation.
A few weeks before that, police in Mexico found 12 bodies in a truck – believed to be the victims of a deadly gang war between feuding drug cartels.
The bodies were discovered on a stretch of motorway in the Huetamo region of Michoacán state in central Mexico, 450km from the capital Mexico City.
The unidentified victims were found in the back of a red pick-up truck with licence plates for the neighbouring state of Guerrero, according to official reports.
The grotesque discovery found the bodies had been stacked in the back of the van and hidden under a cover.
At the end of January Guanajuato saw its deadliest few days of the year, bringing the total number of assassinations in the state this year to 301 after 3,540 were murdered last year