Five men who purportedly carried out the attack on four Americans last week have been found dumped on a street in the city of Matamoros, with an apology note claiming to be from the fearsome cartel that controls much of Tamaulipas state. The five men were discovered with their hands tied, shirts pulled over their heads and bare chests to the pavement. Nearby, a note in black marker read: “We’ve decided to hand over those involved and directly responsible in the events who acted at all times under their own free will.” The discovery is the latest bizarre development in the kidnapping case of four Americans that left at least three people dead and set off a diplomatic firestorm between two neighboring countries. The kidnapping, which took place last Friday, came to an end on Tuesday when the four US citizens were reportedly found by Mexican authorities, two of them dead, the two survivors shortly returned to US soil. The Americans had crossed into Mexico, where one of them reportedly planned to have a tummy tuck procedure, before they were confronted by gunmen who detained them and took them away. Mexican authorities said they believe it was a likely case of mistaken identity. The speed at which the four were found, involving a taskforce including the Mexican military, national guard and state police, was met with indignation among opposition politicians and human rights activists in Mexico, a country where more than 100,000 people are missing and crimes are rarely solved. “We live in a country where thousands of people go missing every year, and authorities rarely do anything to try to find them or identify those responsible,” said Tyler Mattiace, a Mexico researcher at Human Rights Watch. “It is truly remarkable that authorities have acted so swiftly to resolve this case involving four Americans.” The kidnapping also sparked outrage across the border in the US, where some Republican lawmakers went so far as to call for the military to intervene in order to tackle the cartels and the surging violence they have wrought. South Carolina senator Lindsey Graham said he planned to introduce legislation to designate cartels as foreign terrorist organizations and give the US military the authority to confront them. “Drug cartels in Mexico have been terrorizing Americans for decades,” Graham said in a press conference on Tuesday. “We’re going to unleash the fury and the might of the United States against these cartels.” The senator’s plan to name cartels as terrorist groups was quickly rejected by the Biden administration. “Designating these cartels as [terrorists] would not grant us any additional authorities that we don’t really have at this time,” said White House press secretary, Karine Jean-Pierre, on Wednesday. “The United States has powerful sanctions authorities specifically designated to combat narcotics-trafficking organizations and the individuals and entities that enable them.” The proposal has also been met with furor in Mexico, where President Andrés Manuel López Obrador, known popularly as Amlo, has spent much of his presidency railing about the importance of Mexican sovereignty, particularly in terms of national security. “We are not going to permit any foreign government to intervene in our territory, much less that a government’s armed forces intervene,” Amlo said during his daily news conference on Thursday. “In addition to being irresponsible, it is an offense to the people of Mexico,” he said, adding that Mexico “does not take orders from anyone”. The Tamaulipas state prosecutor’s office said on Thursday that local authorities had secured an ambulance that was used to take the Americans to a local clinic for first aid, apparently by the armed group that first kidnapped them. It is not yet clear whether the five men found in Matamoros on Wednesday night have any actual link to the kidnapping, despite the insistence of the typo-riddled note supposedly signed by the Scorpions, the armed wing of the Gulf cartel that dominates Tamaulipas state. The Gulf cartel “asks the community to be calm”, it reads. “We are committed that the mistakes caused by lack of discipline are not repeated and that those responsible are made to pay, no matter who they are!!”