Locals speak of large numbers of cartel hitmen roaming the dirt roads linking the tiny villages and towns dotted around the mountains. They say the gunmen have displaced dozens of families. They warn outsiders not to venture into the area.
Something is seriously amiss in the municipality of Badiraguato, located in the dry and rugged mountains of Mexico's northern state of Sinaloa that is the birthplace of some of the country's most notorious crime lords, including Joaquín "El Chapo" Guzmán.
Recent reports of violence could be a sign that Chapo's arrest in January, six months after he escaped from maximum-security jail, may have emboldened old rivals to such a degree that they have now launched an incursion into what was once considered his impenetrable territory.
Local paper Rio Doce reported that, last Saturday, a group of 150 gunmen even ransacked the mansion Chapo built for his mother in the tiny village of La Tuna, where the drug lord grew up.
The paper said three people died in the attack. It also reported that gunmen scoured the nearby villages of Arroyo Seco and San José del Barranco, robbing residents of their vehicles.
Citing sources within the Badiraguato municipal government, the Noroeste newspaper said between 200 and 350 families fled the area for fear of further bloodshed.
The displaced reportedly went to the main urban center in the municipality, Badiraguato, several hours' drive away from the hamlets at the center of the conflict. Some have reportedly left the mountains altogether, and headed for the state capital of Culiacán.
Daily paper La Jornada cited unofficial sources saying that Chapo's mother, 86-year-old Consuelo Loera, was flown out of the area in a helicopter and was later taken to Mexico City.
"A direct attack against the family of Guzmán is without precedent," said Javier Valdez Cárdenas, a reporter from Rio Doce. "It could be the sign that old accounts will be settled."
VICE News was unable to confirm the attack in La Tuna, but several residents did talk of the wave of violence, and said they had a sense that the area is on the verge of a major turf war.
"It's very tense in the mountains, very dangerous," said one resident of the town of Badiraguato. "There's violence in the hamlets out there and we're scared that it may come to the main town soon. People have fled the area, we've seen them here in our town."
The resident, who asked to remain anonymous out of concerns for his safety, said that the mountains have been "heating up" for at least two to three weeks.
"I've heard of the killings of seven people since the beginning of this month," he said. "There are large groups of armed men roaming the mountains. They're looking for specific targets. They're telling people to leave their communities so that no innocents are killed."
The authorities have given only limited and vague information about what is happening in the area. Sinaloa governor Mario López Váldez confirmed to reporters on Thursday that a group of armed people had indeed "intruded" in the area, but said no deaths or gunfights had been confirmed. He described the incident as a "dispute between families".
But even a family feud is not something to take lightly in Badiraguato, locals said.
Several residents said they had information indicating that the attacks were ordered by Isidro Meza Flores — known as El Chapito, or El Chapo Isidro — one of a new generation of leaders in the Beltrán Leyva cartel.
The Beltrán Leyva's trafficking organization, founded by four brothers who also grew up in the same area, was once closely allied to El Chapo within a broader group of traffickers known as the Sinaloa Federation. They became bitter rivals after the arrest of Alfredo Beltrán Leyva in 2008. Many said the military found him thanks to information from Chapo.
The split provoked several years of bloody gangland warfare in the state, which cost hundreds of lives and left all four Beltrán Leyva brothers dead or in prison, and many more old resentments to fester.
One source said it seemed Meza Flores sent a large group of his men to the area to search for and kill one of Chapo Guzmán's brothers. They said the original request came from one of Alfredo Beltrán Leyva's sons.
The Beltrán Leyva brothers grew up in La Palma, a hamlet less than two miles from La Tuna. VICE News visited both communities in January, in the wake of Guzmán's rearrest.
The single winding dirt road that connects the two communities leads past a luxurious mansion known as La Herradura, or The Horseshoe, said to belong to Alfredo Beltrán Leyva.
The huge red- and yellow-painted home built for Chapo Guzmán's mother stands a stone's throw further up the road.
Local sources said in January that the drug lord himself had visited his mother several times during the six months he was on the run.
If the attacks on that building are confirmed it would be an assault on one of the clearest symbols of the international drug trafficking empire he created and maintained for many years despite a massive government crackdown on organized crime supported by the US.
It could finally be a sign that, as he awaits near-certain extradition to the United States in a prison near the border city of Ciudad Juárez, El Chapo Guzman's once-legendary power may be permanently broken.
Watch: Displaced in Sinaloa: The Hunt for 'El Chapo'
Follow Jan-Albert Hootsen on Twitter: @Jayhootsen