MEXICO CITY (AP) — The government of El Salvador said Wednesday that two of its migrants, including a 17 year-old, died when two Mexican soldiers opened fire on the truck they were riding in last week.

Another underage migrant, an 11-year-old Egyptian girl, also died in the shooting along with her 18-year-old sister. Both soldiers have been relieved of duties and turned over to prosecutors.

A total of six migrants died when the soldiers shot up the truck after they claimed to have heard “detonations” prior to opening fire. Mexican officials have said the other two migrants killed were from Peru and Honduras.

But Mexican officials have steadfastly refused to confirm the details about the victims, casting doubt on newly inaugurated President Claudia Sheinbaum’s pledges of transparency and respect for human rights.

The shootings occurred on Oct. 1 — Sheinbaum’s first day in office — near the city of Tapachula, near the border with Guatemala. The area is often used by migrant smugglers, but warring drug cartels also operate in the region.

El Salvador's Foreign Ministry demanded a thorough investigation into the events that lead up to the deaths of the 17-year-old boy and a 57-year-old man.

Previously, Peru’s foreign ministry confirmed one Peruvian was killed and demanded “an urgent investigation” into the killings. Peru and Mexico have had damaged relations since a 2022 diplomatic spat.

It was the worst killing of migrants by authorities in Mexico since police in the northern state of Tamaulipas killed 17 migrants in 2021.