More than 50,000 people in Mexico have been killed in drug-related violence in the past six years.
A normally calm Mexican beach resort popular with American tourists was turned into a “war zone” when a gun battle between security forces and criminal suspects broke out near a luxury hotel.
Five gunmen were killed in the pre-dawn shoot-out in Puerto Penasco, which is across the border from Arizona, on Wednesday, marking another bloody day in Mexico.
Local residents, many of whom are foreign expatriates, reported hearing helicopters flying over their houses and gunfire.
"We weren't sure what the heck was going on. I heard the gunfire," said Stephen Heisler, 47, who lives in the city with his wife and two small children.
"It was pretty intense stuff. And we didn't know if the helicopter was friend or foe – we could see it shooting – so we took cover.
"If you can imagine the US Marines coming out for an incident in Los Angeles, that's what happened here. It was a war zone."
Puerto Penasco is located in the state of Sonora which has been the scene of turf battles between the Sinaloa drug cartel and rival gangs fighting for control of lucrative smuggling routes into the US.
Also on Wednesday, but on the other side of the country, five teenagers waiting for a bus were killed when they were run over by armed men fleeing soldiers in the northeastern border city of Reynosa.
The men lost control of their pick up and ploughed into the group, before escaping.