President TrumpDonald John TrumpHillary Clinton urges Democrats to pick a candidate who can win the Electoral College Shimkus announces he will stick with plan to retire after reconsidering Rand Paul demands media print whistleblower's name MORE on Tuesday spoke with Mexican President Andrés Manuel López Obrador to condemn an ambush in northern Mexico that left nine U.S. citizens dead.

Trump and López Obrador discussed the incident, which is believed to have ties to organized crime in Mexico, and efforts to combat drug cartels and other criminal groups in the country.

"President Trump made clear that the United States condemns these senseless acts of violence that took the lives of nine American citizens and offered Mexico assistance to ensure the perpetrators face justice," deputy White House press secretary Hogan Gidley said in a statement.

López Obrador said in his own statement that he expressed condolences to Trump about the deaths of the American citizens and "thanked him for his willingness to support us." He also told Trump that the Mexican government would carry out justice in the case.  

A través del presidente Trump, envié mi más profundo pésame a los familiares y amigos de quienes fueron asesinados en los límites de Chihuahua y Sonora.

Le agradecí su disposición de apoyarnos y le informé que las instituciones del Gobierno de México actúan para hacer justicia. pic.twitter.com/nyls6gix86

— Andrés Manuel (@lopezobrador_) November 5, 2019

López Obrador earlier in the day knocked down Trump's offer to partner with Mexico to "to wage WAR on the drug cartels and wipe them off the face of the earth."

Nine members of a prominent Mormon family, including six children, were killed Monday in an ambush in northern Mexico in a region with a history of violence.

The New York Times reported that the members of the LeBarón family were dual Mexican and American citizens who have lived in a fundamentalist Mormon community in the border region for decades. The group was traveling in three separate vehicles when gunmen reportedly opened fire on them.

Mexican officials said criminal groups fighting for control of the region may have confused the vehicles for a rival organization. Among the groups linked to that area is the Sinaloa Cartel.

López Obrador, who made ending the war on drugs one of the pillars of his campaign, has been under increasing internal pressure to ratchet up enforcement against the cartels after widespread violence killed 13 people on Oct. 17 in the northern city of Culiacán.

Trump meanwhile has made cracking down on the flow of migrants across the southern border a hallmark of his administration. The president often portrays those seeking to enter the U.S. as hardened criminals who come from gangs and have violent backgrounds.