In this July 20, 2021 file photo, Prime Minister Ariel Henry, center, talks with former interim Prime Minister Claude Joseph as they stand surrounded by Henry’s cabinet after his appointment in Port-au-Prince, Haiti, weeks after the assassination of President Jovenel Moise at his home. Henry faces increased scrutiny from authorities investigating Moise´s slaying. (AP Photo/Joseph Odelyn, File)

Haiti’s government is starting to crumble as Prime Minister Ariel Henry faces increased scrutiny from authorities investigating the president’s slaying, with one top official resigning Wednesday as he accused Henry of obstructing justice in a sharply worded letter.

Rénald Luberice, who served more than four years as secretary general of Haiti’s Council of Ministers, said he cannot remain under the direction of someone who is under suspicion and who “does not intend to cooperate with justice, seeking, on the contrary, by all means, to obstruct it.”

Luberice also said he is concerned about the alleged evidence against Henry in the killing of President Jovenel Moïse.

“May each minister put himself at the height of his mission at this historic crossroads,” he said.

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A spokesman for Henry declined to comment.

Last week, former Port-au-Prince chief prosecutor Bed-Ford Claude asked Henry to meet with him Tuesday to explain why he had two phone conversations with a key suspect just hours after the July 7 killing of Moïse at his home. The suspect, Joseph Badio, was fired from the government’s anti-corruption unit in May and remains a fugitive.

On Tuesday, Claude ordered the judge overseeing the case to charge and investigate the prime minister based on that evidence. Hours later, a new chief prosecutor replaced Claude on orders of Henry.

The developments underline that Moïse’s Tèt Kale party is fracturing, said Robert Fatton, a Haitian politics expert at the University of Virginia.

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Some politicians are aligning themselves with Henry and others are breaking away, threatening to further destabilize the country as it tries to recover from the turmoil of the assassination and a recent earthquake that killed more than 2,200 people as it prepares for upcoming presidential and legislative elections.

Among those breaking away is Senate President Joseph Lambert, a one-time Moïse ally who recently proclaimed himself as provisional president in a move that has only received support from several politicians and has not been recognized by Henry’s administration or anyone in the international community.

“I don’t know how long the power struggle can continue,” Fatton said. “All of it is bewildering. We’ll have to wait to see if the situation settles and if Ariel Henry wins that battle.”

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Henry, who Moïse named as prime minister shortly before he was killed, has not spoken publicly on the issue this week, saying only over the weekend that he is focused on stabilizing Haiti and would not be distracted by summons, maneuvers or threats.

More than 40 suspects have been arrested in the slaying, including 18 Colombian ex-soldiers who have accused Haitian authorities of torturing them while they are in custody. The investigation has faced several setbacks, including death threats that have forced court clerks to go into hiding and a judge to step down after one of his assistants died in unclear circumstances.