Mexico City , Mexico ( CNN ) -- The Chihuahua attorney general 's office said Friday it is investigating whether the car in which two photojournalists were shot Thursday in northern Mexico belonged to a human-rights activist who may have been the intended target . A photographer for El Diario newspaper in Ciudad Juarez was gunned down Thursday , the paper said on its website . A second photographer was wounded in the shooting . Luis Carlos Santiago , 21 , was declared dead at the scene . He and his 18-year-old co-worker , Carlos Manuel Sanchez , were inside a silver Nissan sedan in the parking lot of a shopping mall , the newspaper said . Santiago was in the driver 's seat . Unidentified gunmen followed the pair to the Rio Grande Mall , near the newspaper 's offices , a source with knowledge of the investigation told CNN . At 2:20 p.m. , the gunmen -- who were in a compact gray car -- opened fire , killing Santiago , the newspaper said , citing witnesses . Despite having been struck in the chest and arm , Sanchez got out of the car and entered the mall , the newspaper said . The gunmen continued firing , without striking him again , then left , it reported . The wounded journalist was taken to a hospital in stable condition , the official said . The journalists were using a car that belongs to an attorney and human-rights activist , Gustavo de la Rosa , who lives in the United States , said Arturo Sandoval , a spokesman for the Chihuahua attorney general . Officials were investigating whether the elder de la Rosa was the intended target , he said . De la Rosa 's son , an editor at the newspaper , had loaned the car to the two photojournalists to use to drive to the mall , where they were planning to attend a photography class taught by a newspaper staff member , El Diario reported . Ciudad Juarez is one of the deadliest cities in Mexico , with 2,185 killings since January 1 and the country is one of the most dangerous for journalists . Much of the violence stems from turf wars between rival cartels and battles between the cartels and the Mexican authorities . The source said it was not clear whether Thursday 's killing was related to drug violence . The gunmen used 9mm handguns , the official said . The newspaper reported Friday that witnesses cited at least two gunmen . Santiago is the ninth journalist killed in Mexico this year , according to the Committee to Protect Journalists . Drug cartels pressure journalists and editors in Mexico to avoid reporting on them and to print unflattering stories about rival drug cartels . The result has been increasing self-censorship from many media outlets throughout the country . Press freedom organizations say Mexico does not do enough to investigate the killing of journalists . A recent CPJ report found `` systemic failures that , if left unaddressed , will further erode freedom of expression and the rule of law . Vital national and international interests are at stake . '' CNN 's Nick Valencia contributed to this story .
1 journalist killed , at least two wounded in Juarez . A human-rights activist may have been the target . Mexico is the second journalist killed this year in Santiago .