The Associated Press says that law enforcement has found a letter from a group of Mexican drug cartel apologizing for the kidnapping and murder of two U.S. citizens. The letter, signed by the Gulf cartel’s Scorpion group, apologized to the victims and their families—including a Mexican woman killed in the shooting—and citizens of Matamoros, Mexico, where the Americans were kidnapped, according to the Associated Press. The cartel also condemns the violence, noting that the persons responsible for the kidnapping violated the cartel’s tenet of “respecting the lives and well-being of the innocent,” according to the AP. According to the AP, the faction wrote that it had handed over the individuals responsible for the kidnapping to law enforcement. The AP has not yet confirmed whether Mexican authorities have detained other people in response to the letter.