CNN  — 

Nine members of a family from a Mormon community were killed on the Mexican side of the border with the United States, and a relative of one of those massacred told CNN on Tuesday the family is no stranger to drug cartel violence.

This photo shows Howard Jackob Miller, Jr., Rhonita Maria Miller, infant twins Titus Alvin Miller and Tiana Griciel Miller, and Krystal Bellaine Miller, who all died in the attack.  Howard Miller, the adult male pictured, is alive and was not present at the attack.

Kendra Lee Miller, whose sister-in-law Rhonita Maria Miller died in the attack, said, “Cartels have taken too many of our family members” and those killed Monday were “not the first.”

Miller told CNN her family has recently been threatened by cartels over where it can travel.

Investigators believe three vehicles traveling between the states of Sonora and Chihuahua were ambushed by criminal groups Monday evening, Mexican authorities said.

The victims include three women, four small children and two infants, family member Alex LeBaron said from Mexico. All were dual US-Mexican citizens, he said.

The victims were “all shot while in vehicles while driving,” LeBaron told CNN. Eight children survived.

“Women and children were massacred, burned alive,” LeBaron said. “Mothers were screaming for the fire to stop.”

‘Long-standing tensions’

The LeBaron family’s history of conflict with Mexican drug cartels may indicate the family was targeted, former Mexican Foreign Minister Jorge Castañeda told CNN on Tuesday evening.