PORT-AU-PRINCE, Haiti — The head of palace security for President Jovenel Moïse, who was assassinated last week at his home, was taken into police custody on Thursday, deepening investigators’ focus into the possibility that Haitian insiders had eased the killers’ path.
The palace security chief, Dimitri Hérard, made several stopovers in the Colombian capital, Bogotá, in the months before the assassination. Haitian officials say a group of former soldiers from Colombia, whom they accuse of acting as mercenaries, played a central role in the killing.
On Thursday, the Pentagon also confirmed that some of those Colombian veterans had received training from the United States military, as part of a cooperation between security forces that has stretched for decades. Family members said that one them was the chief recruiter for the mercenary force, Duberney Capador, 40.
The revelations came as officials in Haiti, Colombia and the United States all raced to determine who was ultimately behind the assassination of Mr. Moïse, and the aims and means of the conspirators.
On Thursday, the Colombian police said the two leaders of the Colombian veterans, Mr. Capador and retired Capt. German Alejandro Rivera, conspired with Haitian suspects as early as May to detain the president.
Colombia’s police commander, Gen. Jorge Luis Vargas, told reporters that it remained unclear when a plan to kidnap Mr. Moïse turned into a killing. He said that seven Colombian operatives entered the presidential residence on the night of the attack, while the rest guarded the area.
The detention of Mr. Hérard, the palace security chief, was confirmed by Marie Michelle Verrier, a spokeswoman for Haiti’s National Police. Mr. Hérard was one of four members of the president’s security personnel whom the state prosecutor was planning to call in for questioning earlier this week, as questions remained over how the attackers managed to enter the heavily guarded home.
The head of the presidential guard and two other top bodyguards had also been called in for questioning, Bedford Claude, the chief public prosecutor in Port-au-Prince, the Haitian capital, said earlier this week. He had issued summons for the four to appear as part of the investigation into the assassination.
And on Wednesday night, Haitian officials said they had detained two other men they suspected of being involved — identified as Reynaldo Corvington and Gilbert Dragon — and who were each found to be in possession of a cache of weapons.
Questions have focused on reports that none of Mr. Hérard’s security force fired a shot despite the approach of two dozen armed mercenaries, their entry into the presidential compound, and the eruption of gunfire that killed Mr. Moise and seriously injured his wife.
In Washington, a Pentagon spokesman confirmed that some of the Colombians had received training by the U.S. military as part of a long-term cooperation between the countries.
“A review of our training databases indicates that a small number of the Colombian individuals detained as part of this investigation had participated in past U.S. military training and education programs, while serving as active members of the Colombian Military Forces,” the spokesman, Lt. Col. Kenneth L. Hoffman, said in a statement.
The Pentagon’s review is still underway, said Colonel Hoffman, who declined to say exactly how many men received training, when or where they received it, and what the instruction entailed. A U.S. official said that the military has so far identified about half a dozen Colombians who previously received American military instruction.
The disclosure that some the Colombian suspects had received American military training was previously reported in the Washington Post.
The Pentagon, including its Army Green Berets, has conducted training for thousands of military service members in countries across Latin America over the past several decades. Colombia, in particular, has been a significant American military partner for many years, receiving billions of dollars since 2000 in its effort to battle drug-trafficking organizations, leftist guerrillas and far-right paramilitary groups.
Some of the U.S. training of Colombian soldiers likely happened in Colombia. But Mr. Capador, who recruited the Colombian veterans, traveled to the United States for his training, according to dozens of interviews with family members of the recruits, and with men who were recruited by Mr. Capador but ended up not going to Haiti.
Mr. Capador is among the three Colombians killed in the aftermath of the assassination.
Interviews with family members also revealed that several of the Colombian veterans had served in the international peacekeeping mission in the Sinai Peninsula in Egypt. The deployment instilled them with a sense of purpose and camaraderie, and led at least some of them seek other foreign assignments after retirement, the relatives said.
Mr. Capador had traveled to the United States to do “human rights” training, according to his sister, Yenny Carolina Capador. It is unclear whether Mr. Capador made any long-lasting contacts within the United States during that time.
U.S. military officials say the training emphasizes respect for human rights and compliance with the rule of law. American lawmakers have long accused the Colombian military of targeting civilians, violating the laws of war and lacking accountability.
Senator Patrick J. Leahy, Democrat of Vermont, was behind legislation that bars training or equipment to foreign troops or units who commit “gross human rights violations” like rape, murder or torture
“We want our training of foreign armies to build professionalism and respect for human rights, but we should not be naïve about the impact of our training,” Mr. Leahy said in a statement on Thursday. “If a foreign army has a history of violating human rights, as Colombia’s does, it is hard to change that unless the perpetrators are punished.”
In Colombia, the defense minister said during a news conference this week that Mr. Hérard, the detained Haitian palace security chief, had transited through Bogotá six times this year on his way to other Latin American countries, stopping for two days or more on at least one occasion.
Last week, Mr. Hérard declined to respond to questions from The New York Times, texting: “Unfortunately, after consulting with my lawyer, I am not in a position to comment on this at the very moment as this is an open investigation and a matter of national security.”
When asked, he did not provide the name of his lawyer.
On Thursday, President Biden made his most definitive statement yet on sending U.S. troops to Haiti, rejecting a plea for military assistance made last week by the country’s interim leaders.
“The idea of sending American forces into Haiti is not on the agenda at this moment,” Mr. Biden said during a news conference with Chancellor Angela Merkel of Germany.
Mr. Biden added, however, that additional Marines were being deployed to augment embassy security.
“We’re only sending American Marines to our embassy to make sure that they are secure and nothing is out of whack at all,” he said
Reporting was contributed by Anatoly Kurmanaev, Julie Turkewitz, Ernesto Londoño, and Chris Cameron.