The Mexican government is continuing its efforts to identify those responsible for the deaths of 17 Mexican migrants who died during encounters with U.S. Immigration and Customs Enforcement (ICE). Foreign Affairs Undersecretary Roberto Velasco said on Wednesday that Mexico has filed 20 complaints with U.S. authorities, only four of which have received a response. The Foreign Ministry has spent more than $24,000 repatriating the bodies and has maintained a formal request to the Justice Department for an investigation into the causes of the deaths.

“We want an investigation to be carried out and, if any member of ICE, or any private contractor responsible for running or overseeing a detention center, was responsible, then action should be taken. There are simply too many cases,” said Mexican President Claudia Sheinbaum.

One state prosecutor has responded to Mexico’s complaint by backing ICE’s account. The official, from Florida, upheld the immigration agency’s investigation into the death of 19-year-old Royer Pérez, the youngest Mexican victim.

Pérez was arrested in January by police in Volusia County, northern Florida, and charged with identity theft and resisting arrest. He was transferred to a state detention facility, where he later died despite efforts to revive him. The official account initially pointed to suicide, but testimony from detainees and a preliminary report from the local medical examiner’s office suggested he was killed by guards. Mexico has repeatedly called for the circumstances surrounding his death to be clarified, but U.S. authorities have so far declined to open any additional investigation.

Four other state prosecutors, from Illinois, California, Texas and Florida, as well as district attorneys in Oxnard, San Bernardino, Chicago and Atlanta, have also replied, but only to acknowledge receipt of Mexico’s complaints. The government is still awaiting formal responses.

Of the 17 deaths recorded, at least four occurred inside the Adelanto immigrant detention center in California. The victims were Alberto Gutiérrez Reyes, Ismael Ayala Uribe, Gabriel García Avilés and José Guadalupe Ramos Solano. Their families and civil society organizations allege negligence, mistreatment and inadequate medical care.

Sheinbaum’s administration has also filed a complaint with the Department of Homeland Security and ICE officials demanding accountability from the private companies that manage detention facilities. Among them is GEO Group, which operates Adelanto and several other migrant detention centers. The company has faced longstanding allegations of medical negligence, excessive use of force, overcrowding, sexual abuse, unsanitary conditions and inadequate food.

Meanwhile, Volker Türk, the United Nations High Commissioner for Human Rights, has responded to a letter from the Mexican government raising concerns about the deaths of Mexican migrants in U.S. state custody.

“He informed us that he had forwarded the information to the U.N. Human Rights Council for its independent consideration. He will continue to monitor conditions in detention centers and the human rights of migrants, and he called on U.S. authorities to conduct prompt investigations,” Velasco said.