Two Americans were rescued, and two others were found dead Tuesday after they were assaulted and kidnapped in Mexico last Friday.

Officials from the United States Embassy and Consulates in Mexico announced in a press release on Sunday that four U.S. citizens traveling in a white minivan marked with North Carolina license plates crossed from Brownsville, Texas, into the Mexican border town of Matamoros on March 3.

Shortly after the minivan crossed the border, a group of armed assailants reportedly opened fire on the vehicle. All four occupants were captured by the gunmen and loaded into the back of a pickup truck.

Officials believe the Americans were not specifically targeted but merely caught in a drug cartel shootout.

Initially, Mexican President Andrés Manuel López Obrador said the four Americans were attempting to buy medicine when they were caught in the crossfire between two armed groups, according to WFAA. However, it was later confirmed that one of the individuals in the group had gone to Matamoros for a cosmetic surgery procedure.

“The FBI, federal partners, and Mexican law enforcement agencies are investigating. The FBI is announcing a reward of $50,000 for the return of the victims and the arrest of those involved,” the news release stated.

On Tuesday, the two surviving victims were found under guard in a wooden shack east of Matamoros. One of the survivors was wounded in the leg. One man allegedly holding them hostage was arrested.

The survivors, identified as 38-year-old Eric Williams and Latavia McGee, were escorted to Brownsville by Mexican military Humvees and armed National Guard trucks, The Wall Street Journal reported.

The bodies of the two deceased victims were found in a field near the shack. Following forensic work at the Matamoros morgue, the bodies will be turned over to U.S. authorities.

The deceased victims were identified as Shaeed Woodward, 33, and Zindell Brown, who was said to be in his mid-20s.

White House National Security Council spokesperson John Kirby said the U.S. is collaborating with the Mexican government to conduct a full investigation into the kidnapping and subsequent killings.