Eleven people were killed in . a gunfight in western Mexico when suspected gang members . ambushed a police convoy . Five members of Mexico 's new militarized police , or gendarmerie , were killed in one of the deadliest attacks on . security forces since Mexican President Enrique Pena Nieto took . office in December 2012 . The shootout take place around 9.15pm Thursday in . Ocotlan , Jalisco state , and eight others were wounded , the . National Security Commission said in a statement on Friday . WARNING GRAPHIC CONTENT BELOW . Eleven people , including five members of Mexico 's militarized police , were killed after a gunfight in the city of Ocotlan , Jalisco . Gendarmerie police had been patrolling the area of southwest Mexico when a pickup truck approached and opened fire . It is the deadliest attack on the forces since President Enrique Pena Nieto took office . Two thousand shell cases were found at the site of the gunfight , which lasted for half an hour and killed three bystanders . Three bystanders who apparently had nothing to do with the . ambush and three suspected gang members were also killed during a gunfight that lasted 30 minutes , according to AFP . Seven vehicles of the new 5,000-strong gendarmerie were patrolling the town southeast of the . state capital Guadalajara , the commission said . At least 10 vehicles took part in the attack on police , which began with assailants in a pickup truck firing with high-powered rifles before being . beaten back , the security commission said . Some of the attackers continued to fire as they fled into Ocotlan , a town of around 90,000 people . Authorities originally said that ten people had been killed , but added another bystander to the total late Friday , according to Cronica Jalisto . Two thousand bullet casings were reportedly found at the scene , which was riddle with bullet holes . Authorities originally said that ten people had been killed in the gunfight , though it was later revealed that a third bystander had died . Ten vehicles ( pictured ) are thought to have participated in the attack on the gendarmerie , who suffered their deadliest attack since being created by the president . Police confiscated seven firearms and four fragmentation . grenades at the scene , as well as five vehicles believed to have . belonged to the assailants , the government said . Three civilians killed wearing cartridge belts were assumed to be part of organized crime , and had tactical equipment on them . Jalisco has been plagued by fighting between the Jalisco New . Generation drug cartel and the Knights Templar , a drug gang from . the neighboring state of Michoacan . The gang in southwestern Mexico has been gradually . weakened by the capture or killing of its leaders . More than 100,000 people have been killed in gang-related . violence in Mexico over the past eight years , many of them near the US border . Bringing peace to Mexico was President Enrique Pena Nieto 's . first promise when he took office in 2012 . The gendarmerie was . unveiled to spearhead the government 's efforts to restore order . It began operating last summer , albeit on a smaller scale than . first envisaged . More than 100,000 people have died from gang violence in Mexico over the last eight years , though many of them were near the US border . Violence against the police took place on several streets of Ocotlan , a town of about 90,000 people in Jalisco state . The Jalisco New Generation has been weakened after authorities ( pictured ) captured or killed its leaders . However , violence still plagues the area .
Three suspected militia members killed in clashes in Ocotlan , Jalisco state . homicide is deadliest for gendarmerie police since president created them . Two improvised bullet casings occurred where ten vehicles ambushed them .