Indonesian military chief Gatot Nurmantyo was invited by the chairman of the Joint Chiefs of Staff to attend a conference on Monday and Tuesday in Washington. (Beawiharta/Reuters)

Indonesian leaders are seeking answers after the country’s military chief, Gen. Gatot Nurmantyo, was denied entry to the United States over the weekend.

Nurmantyo had been invited by Gen. Joseph F. Dunford Jr., chairman of the Joint Chiefs of Staff and the United States' highest-ranking military officer — to attend a conference on countering violent extremism on Monday and Tuesday in Washington.

Nurmantyo, his wife and four Indonesian officials were scheduled to leave Indonesia on Saturday evening, local time. Before departure, however, their airline informed them that U.S. Customs would deny their entry, according to the Associated Press.

In a statement, the U.S. Embassy in Jakarta said U.S. Ambassador Joseph Donovan had apologized to Indonesian Foreign Minister Retno Marsudi “for any inconvenience to General Gatot” and would accommodate Nurmantyo’s travel. “The U.S. Embassy was, and remains, prepared to facilitate the General’s travel to the United States,” the U.S. Embassy said. “We remain committed to our Strategic Partnership with Indonesia as a way to deliver security and prosperity to both our nations and peoples.”

The brief statement was at odds with efforts by Indonesian officials to demand an explanation for why Nurmantyo was denied entry to the United States. According to the Jakarta Post, Marsudi met with an official at the U.S. Embassy in Jakarta on Monday morning but was not given further details.

“They said it was still Sunday night in Washington, but I told her the Indonesian government urgently needed to receive clarification,” Marsudi said, according to the newspaper.

Representatives at both the U.S. Embassy in Jakarta and the Embassy of Indonesia in Washington were not available to comment Monday morning.

U.S. Defense Secretary Jim Mattis, who is in the Philippines to meet with defense ministers in the region, also pulled aside Indonesian Defense Minister Ryamizard Ryacudu to apologize for the issue, a Pentagon spokesman told The Washington Post.

Aaron Connelly, a research fellow with the Lowy Institute for International Policy, said the denial was probably just an administrative mistake, but also one that Nurmantyo could use politically, given his strained relationship with Indonesia’s president and other top officials.

“I think it’s worth emphasizing, given Gatot’s history, he’s not the most credible witness, so his version of events may not be a full reading of what has happened,” Connelly told The Post. “But it puts the president and the foreign minister and the chief security minister . . . on the spot to have to defend Gatot, because he has now aligned himself with the Indonesians’ sense of national honor.”

The incident, he said, led Indonesia’s major news websites and television broadcasts over the weekend. “It is something that people are paying close attention to,” Connelly said. “It folds into a long narrative about the U.S. not respecting Indonesian military . . . and this ongoing political drama that involves Gatot’s political ambitions.”

Indonesia was one of the 43 attending nations at last year's Chiefs of Defense Conference on Countering Violent Extremism. Dunford, who also hosted the 2016 conference, said then that he hoped the conference discussions would allow them to “develop a network of cooperation” and better understand the nature of violent extremism.

Dan Lamothe contributed to this report.

Read more:

Indonesia might be copying the vigilante violence of Duterte’s drug war

It’s not illegal to be gay in Indonesia, but police are cracking down anyway

An Indonesian man disappeared. Villagers found his body inside a 23-foot-long python.

‘Monkey selfie’ lawsuit finally settled after two years and a banana boat full of puns