Two Arizona women were killed Friday morning when gunmen opened fire on their vehicle in the northern Mexican state of Sonora, Mexican authorities said.

The victims, aged 72 and 82 and originally from the town of Caborca, Sonora, were found dead around 10:30 a.m. in an overturned, bullet-riddled white Nissan Pathfinder on the Sonoyta-Caborca ​​highway, the Sonora Attorney General’s Office said in a news release.

Mexican authorities conducted a search and located a vehicle believed to be linked to the suspects, described as a stolen Ford F150, which was found abandoned in the Sonoran city of Quitovac. Inside the vehicle, authorities found four firearms, dozens of rounds of ammunition and bulletproof vests, the attorney general’s office said.

Officials did not immediately give a motive for the attack, although there have been several incidents of cartel violence in Sonora in recent years.

In June 2023, a Ph.D. student from California was found dead in an SUV in Sonorashot seven times after he disappeared while crossing the border to do horticultural research.

In March, prosecutors in Sonora said seven bodies had been found near the Gulf of California town of Puerto Peñasco. The victims were all men in military fatigues and had all been shot to death.