MEXICO CITY (Reuters) - Authorities in Mexico are investigating the murder of two indigenous brothers and sending a special team to a far-flung village to protect other members of the Huichol tribe, the governor of the state of Jalisco said on Monday.

The double homicide comes amid a resurgence in violence from warring drug cartels and follows a spate of unsolved killings of journalists and activists this year that has stirred concerns of broadening attacks.

“I’ll be watching for the report from the team sent as well as the results of the investigation. The Wirraritari can count on us,” Jalisco Governor Aristoteles Sandoval said on Twitter, using another name for the Huichol.

One of the brothers, Miguel Vazquez, was until a couple months ago, a Huichol leader tasked with defending 240,000 hectares (593,000 acres) of native land in Jalisco, according to the University of Guadalajara that once worked with him on a cultural program.

Vazquez had helped repel cattle ranchers that encroached on Huichol lands and said that drug traffickers were trying to force native farmers to grow poppy to make heroin, local newspaper La Jornada reported. His brother, Agustin, also defended tribal lands.

The brothers’ suspected killers belonged to a criminal cell that operates on the border of the states of Jalisco and Zacatecas, the prosecutors’ office of Jalisco said in a statement on Sunday without offering details.

One of the brothers died in the hospital after armed men shot him late on Saturday, the prosecutors’ office said. The second brother was shot dead as he was leaving the hospital that night.

Jalisco is home to the rising Jalisco New Generation Cartel, which Sandoval has said is now Mexico’s biggest drug-trafficking organization.

In January, Isidro Baldenegro, a leader of the Tarahumara tribe and a prominent environmental activist, was shot dead in the northern state of Chihuahua.

The University of Guadalajara called on local and national authorities to give special attention to indigenous leaders because of risks they face in remote regions with scant policing.