A Mexican cartel appears to have written an apology letter after the kidnapping and killing of Americans, saying it went against their rules of 'respecting the life and well-being of the innocent'

• Four Americans were kidnapped and two were killed after entering Mexico last week.
• An apology letter obtained by AP claims to be from the cartel that was responsible.

The Mexican cartel blamed for the kidnapping and killing of Americans appears to have apologized in a letter, saying they are turning over the people involved and that it was against their rules.

The letter was obtained by The Associated Press from an unnamed law enforcement official in the Mexican state of Tamaulipas. The four Americans were abducted in Matamoros, Tamaulipas, on Friday after crossing the US-Mexico border and getting caught in an armed confrontation between groups.

Two were later found dead while the survivors returned to the US for medical treatment.

The letter, which was supposedly written by the Scorpions faction of the Gulf cartel, denounced the kidnapping and killings and apologized to local residents, including a woman who had died during the initial confrontation in which the group was taken, AP reported. The letter also apologized to the Americans and their families.

"We have decided to turn over those who were directly involved and responsible in the events, who at all times acted under their own decision-making and lack of discipline," the letter said, according to AP.

The letter added that the actions did not align with the rules of the cartel, such as "respecting the life and well-being of the innocent."

The letter was accompanied by a photograph of five men, but it's unclear if the suspects were in custody. Law enforcement officials in Tamaulipas did not immediately respond to Insider's request for comment.

Another unnamed Mexican law enforcement official told AP the letter had been found inside a vehicle they had been searching for, with five men tied up inside.

AP reported that cartels sometimes try to protect their image by issuing statements about controversial events that could negatively impact business.

The group of Americans had traveled to Mexico in a white van for a medical procedure before being fired at and taken by armed gunman, according to the FBI. Investigators believed a drug cartel had mistaken the group for smugglers.

Family members have told the media the group of friends traveled to Mexico for one of them to get a tummy tuck procedure. Relatives have identified them as Zindell Brown, Latavia McGee, Eric James Williams, and Shaeed Woodard.

Michelle Williams, the wife of Eric Williams, who is alive, has said she did not know her husband was traveling to Mexico, just that he was "going somewhere to help two friends." Cheryl Orange, another friend who was traveling with the group, said she was unable to cross the border because she didn't have her ID and stayed behind.

Jerry Wallace, the cousin of Eric Williams, told AP about the apology letter: "It ain't gonna change nothing about the suffering that we went through."