Two of the Americans who were kidnapped at gunpoint in a Mexican border city on Friday have returned to the US and are being treated at a hospital, while the remains of the two Americans who were killed are expected to be brought back to the US Thursday. LaTavia Washington McGee, one of the surviving Americans, is expected to come home Wednesday, her mother, Barbara McLeod Burgess, said in an interview with “CNN This Morning.” Burgess also described her understanding of what happened in the harrowing attack. “They were driving through and a van came up and hit them, and that’s when they started shooting at the car, shooting inside the van,” Burgess said. “She said the others tried to run and they got shot at the same time. They all got shot at the same time. And she watched them die.” The other survivor, Eric Williams, was shot in the legs three times and was brought to a hospital in Texas to undergo surgery, his wife, Michele Williams, told CNN. “I was just glad to hear his voice,” she said. Follow live updates Meanwhile, Shaeed Woodard and Zindell Brown were found dead, a US official familiar with the ongoing investigation told CNN. Their remains are expected to be repatriated to the US Thursday, according to a source from the Mexico Attorney General’s office. That’s after a Mexican medical examiner completed a forensic examination to determine their causes of death. Once the bodies are in the US, a second autopsy will eventually be conducted, according to a US official familiar with the investigation. The autopsies concluded Wednesday morning, an official from the Tamaulipas Prosecutor’s Office told CNN. Their impending return home comes a day after the four Americans were found in a “wooden house” in or near the Mexican border city of Matamoros, where they had been kidnapped on Friday, Tamaulipas Gov. Américo Villarreal announced. The tight-knit group of friends had driven to Mexico from South Carolina so Washington McGee – a mother of six – could undergo a medical procedure in Matamoros, two family members told CNN. But after they crossed the border, their car was intercepted by gunmen who fired on the Americans, loaded them into a vehicle and took them from the scene, according to the FBI. An innocent Mexican bystander was fatally struck by a stray bullet almost a block and a half from where the Americans were kidnapped, Villarreal said. One person has been detained in connection with the Americans’ deaths who was undertaking “surveillance functions of the victims,” Villarreal said, identifying the individual as 24-year-old Jose “N.” Officials would not confirm whether the person is connected to a criminal organization. “Attacks on US citizens are unacceptable, no matter where or under what circumstances they occur,” National Security Council Coordinator for Strategic Communications John Kirby said Tuesday. He said the US is working with the Mexican government “to ensure that justice is done in this case.” “Right now, our immediate concerns are the safe return of our citizens, the health and the well-being of those who survived this attack,” Kirby said. Why these Americans were targeted Investigators believe the Americans were targeted by a Mexican cartel that likely mistook them for Haitian drug smugglers, a US official familiar with the investigation told CNN. The official said investigators have not identified any concerning criminal history on the part of the Americans involved. Mexican officials said they are still investigating. Tamaulipas Attorney General Irving Barrios Mojica said the “most viable” motive being considered was that “confusion” led to the kidnapping incident and that it was not a “direct attack.” Mexican President Andrés Manuel López Obrador said Wednesday that political “adversaries” in the US and Mexico were making a “scandal” out of the kidnapping. “We have to finish the investigation to accurately know what happened and inform here what was the cause,” he said. Earlier in the news conference, a presentation by a government-sponsored fact-checking agency made the claim that the Americans were not confused for Haitian drug traffickers – a position contrary to the US official. “It’s false that the US citizens were confused with narcotraffickers. Fake news has circulated on social media about the kidnapping of the American citizens. For example, some suggested that they had been confused with Haitian narcotraffickers or that they were Haitian immigrants,” said an announcer in the fact-checking presentation, which is a weekly segment in the president’s daily news conferences. CNN has reached out to investigators in the US and Mexico, as well as the fact-checking agency, for comment. How the kidnapping and investigation unfolded Information from officials and the victims’ family members as well as video of the kidnapping provide the timeline of what happened. The four friends had booked a hotel in Brownsville, Texas, and were planning on driving across the border to Matamoros for Washington McGee to undergo a cosmetic surgery on Friday, a close friend who did not want to be identified told CNN. Washington McGee had also traveled to Mexico for a procedure a few years ago, her mother said. The country has become a top destination for “medical tourism,” attracting Americans who may be seeking more affordable care or treatments that are unavailable in the US. However, Matamoros is not considered a primary medical destination, and the US State Department has issued a “Do Not Travel” advisory for the state of Tamaulipas, citing organized crime activity and kidnapping. Ongoing violence and organized crime have plagued some Mexican cities as part of the country’s long-running drug war. The group crossed into Matamoros at about 9:18 a.m. Friday, Villarreal said. After becoming lost on their way to the clinic, the friends tried to reach the doctor’s office for directions but were having difficulty because of a poor phone signal, the close friend said. At some point as the friends were driving, unidentified gunmen fired on their minivan and then loaded the Americans into their vehicle and took them away, according to the FBI. A Mexican official said Tuesday that the gunmen were driving a pickup truck. A video obtained by CNN of the incident shows the Americans being roughly loaded into the bed of a white pickup truck. The video shows Washington McGee being tossed onto the bed of the truck by two unidentified people as a third armed man watches, and the men appear to drag at least two limp people onto the truck bed. Burgess, Washington McGee’s mother, told CNN the video showed her daughter being thrown onto the truck “like trash.” Washington McGee’s aunt, Mary McFadden, told CNN earlier this week that the family saw the video and recognized her niece’s blonde hair and clothes. When Mexican authorities arrived on the scene, they noticed the Americans’ van had North Carolina license plates and reached out to US officials, who were able to run the plates, according to Barrios Mojica. Investigators began processing vehicles, obtaining ballistics and fingerprint data, taking biological samples for genetic profiles and gathering surveillance camera footage, Mexican officials said. Police were able to identify the gunmen’s truck, Barrios Mojica said. Officials then initiated “several searches” with different agencies, he said. The Americans had been moved to several places during their disappearance “to create confusion and avoid rescue efforts,” Villarreal said. They were finally found at a house outside Matamoros on Tuesday morning, the attorney general said. US and Mexico tout bilateral efforts Though US law enforcement were not involved in the search on the ground, federal and local agencies in Mexico were cooperating in the effort and a joint task force was created to communicate with US officials, Barrios Mojica said. White House Homeland Security Adviser Liz Sherwood-Randall is leading a high-level US delegation to Mexico this week “to discuss our governments’ ongoing cooperation in combatting illicit fentanyl,” a National Security Council spokesman told CNN on Wednesday. The trip is expected to conclude Thursday, the spokesman said. The visit comes as fentanyl drives a record surge in US overdose deaths, with Mexican drug cartels being the main source of the synthetic opioid. At a news conference Tuesday morning, López Obrador said there was “good cooperation” underway between the two countries on anti-drug efforts. But he has criticized a Republican-led effort to declare the cartels a terrorist organization, arguing that it would infringe on Mexico’s sovereignty. “Now there is cooperation, but with respect to our sovereignty. And President Biden understands that. He’s always been very respectful,” López Obrador said.