The killing of Margarito Martinez Esquivel, a well-respected photojournalist who worked with a number of international outlets, is the second reporter killed so far in Mexico in 2022.
Earlier this month, Jose Luis Gamboa was stabbed to death in Veracruz.
For three years running, Mexico has been considered the most dangerous country for reporters in the world, according to a recent annual tallyfrom the press freedom group Reporters Without Borders.
Martinez had recently complained about threats made against him, and was seeking government protection, according to a reportin the San Diego Union Tribune, one of many outlets to have hired him to help with coverage.
An online fundraiserto cover funeral expenses and support his family has been set up.