June 4, 2012 -- Updated 0810 GMT (1610 HKT) NEW: The attack follows a spate of gruesome incidents in Mexico (CNN) -- Gunmen entered a rehabilitation center in central Mexico and fired on patients, a blog on the Mexican drug war reported. The attack Sunday night left eight people dead and eight others injured, police in the city of Torreon said via Twitter. Family members gathered outside the center as bodies were being removed, according to El Blog del Narco, a blog that publishes information about the Mexican drug war. The attack follows a spate of recent violence in Mexico. Last month, authorities found the decapitated and dismembered bodies of 49 people along a highway in the northern city of Cadereyta, Nuevo Leon. Mexico's interior minister said the 49 deaths were the result of a fierce feud over territory and power between the Zetas drug cartel and members of the allied Gulf and Sinaloa cartels. One of the main suspects, Daniel de Jesus Elizondo Ramirez, was arrested and disclosed details of the brutal slayings, a military official said. Also in May, residents of the border city of Nuevo Laredo found nine bodies hanging from an overpass, along with a message directed to a drug cartel. The five men and four women were hanging from one of the busiest intersections in the city. Analysts have argued that Mexico's economy is thriving, despite widespread violence in a drug war that has claimed more than 47,500 lives since President Felipe Calderon began a crackdown on cartels in December 2006. CNN's Catherine E. Shoichet contributed to this report.