Ten years ago, a relative of the Americans slaughtered in Monday’s Mexican drug cartel massacre was murdered in a neighboring state, allegedly by an individual considered a bloody hitman.

Masked men posing as police killed anti-crime activist Benjamin LeBaron, 31, in Chihuahua state after abducting his younger brother, Eric, from his home in 2009.

“We’re living in a war zone, but it’s a war zone with little kids running all around in the yard,” another brother, Julian LeBaron, told The Seattle Times at the time.

Relatives of the LeBarons were among the three women and six children killed in an ambush Monday in Sonora, blamed on drug cartel gunmen who may have opened fire in a case of mistaken identity. The victims, who held dual U.S.-Mexico citizenship, were in three vehicles on a mountain road. Eight children survived the attack. The youngest of the victims were 8-month-old twins and a 2-year-old boy.

MEXICAN CARTEL MASSACRE: BABY FOUND UNHARMED IN BULLET-RIDDLED VEHICLE; BOY, 13, HID SIBLINGS IN BUSHES

Monday's victims belonged to a religious community in northern Mexico that was founded decades ago as an offshoot of The Church of Jesus Christ of Latter-day Saints.

Before he was killed, Benjamin LeBaron, 31, led protests of his young brother’s kidnapping. The cartel later released Eric LeBaron without its $1 million ransom demand being met, Mexican officials said.

LA MORA, THE MORMON OFFSHOOT COMMUNITY CAUGHT UP IN MEXICO'S BRUTAL DRUG CARTEL WAR

Several months after the murder, Mexican troops captured the suspected killer, Jose Rodolfo Escajeda.

Escajeda was considered one of the bloodiest hitmen in the crime-ridden state of Chihuahua and a leader of the powerful Juarez cartel, Reuters reported.

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Eventually, Escajeda was extradited to Texas stemming on charges stemming from a drug-smuggling incursion across the Rio Grande that led to an armed confrontation with law enforcement officers.

Court records showed Escajeda pleaded guilty to drug charges in 2011 and was sentenced to 35 years in prison.