Reuters reports indicates that the sons of infamous Mexican drug lord El Chapo were likely responsible for the coordinated ambush of a military convoy in Culiacan, Mexico on Friday. The attack killed five soldiers and left 10 others wounded, Reuters reports.

The men successfully captured Julio Ortiz, a detainee being transported by Mexican soldiers in the Sinaloa state. Ortiz was allegedly involved in "a conflict over control of drug crops" that pitted a brother of El Chapo against a rival cartel boss, Reuters reported, but it's unclear whether Ortiz is a friend or enemy of the Sinaloa cartel.

"We aren't sure (about the identity of the attackers), but it's very probable that they work for the sons of El Chapo," General Alfonso Duarte, the regional defense ministry commander in charge of Sinaloa, told reporters in a joint news conference with Sinaloa Gov. Mario Lopez.

Lopez called the attack "cowardly," since "the soldiers, unfortunately, didn't have a chance to defend themselves."

Mexico's president, Enrique Peña Nieto, condemned the attack on Twitter. He said the attacks on the Mexican army "will not go unpunished," adding that those responsible will answer to the law.

One of El Chapo's sons, 29-year-old Jesus Alfredo Guzman Salazar, was kidnapped in Puerto Vallarta in late August by members of the rival drug cartel Jalisco New Generation, though he was released several days later.