Edward Halealoha Ayau, executive director of Hui Malama I Na Kupuna O Hawaii Nei, was taken into federal custody after refusing Chief US District Judge David's Ezra's order to reveal the exact location of the 83 artefacts borrowed from Bishop Museum.
Ayau told Judge Ezra that he would be honoured to be placed in custody. "We did the honourable thing," he said.
Board members William Aila, Pualani Kanahele and Antoinette Freitas, were also found in contempt, but not jailed.
Judge Ezra ordered Ayau to be kept in custody until he or others return the ancient objects or come forward with their location.
The judge said it was not necessary that the objects be returned to the Bishop Museum, but it was necessary that Hui Malama follow the court's order.
"Make no mistake about it, the court's order will be complied with," he said.
The four were called before the court to explain why they have refused to abide by a federal court order and state the locations of the objects and name those who had participated in their reburial.
Hui Malama has told the court that the items have been buried and sealed in the Kawaihae Cave complex on the Big Island.
But Judge Ezra said that the court needs a more precise location to better preserve and protect the artefacts.
Hui Malama said the artefacts were looted from a cave by an archaeologist in 1905 and illegally sold to the museum.
The group argued that it has simply put the items back where they belong. But 13 other groups also claim ownership of the objects.
Sherry Broder, a lawyer for the groups Na Lei Alii Kawananakoa and the Royal Hawaiian Academy of Traditional Arts, which sued Hui
Malama for the objects' return, said Judge Ezra had already bent over backward to accommodate members of Hui Malama.
Judge Ezra said he had hoped that the groups involved could work out their differences but has heard only rhetoric on both sides.
Hui Malama's supporters shouted and wept as the hearing closed and Judge Ezra ordered everyone but the press to leave.
A crowd then gathered just outside the courtroom and began wailing plaintive Hawaiian chants.