Survivors of the worst sea disaster to hit Haitian migrants in years are "angry and revolted" that their crowded boat was rammed twice by a Turks and Caicos vessel before it capsized, killing 61 in shark-filled waters, a senior Haitian official said Wednesday.

Reports about the alleged involvement of the Turks and Caicos boat has taken days to come out because the 78 survivors are locked in a jail-like detention center and barred from speaking to the media.

Officials say about 160 migrants were jammed in the rickety sailboat when it capsized before dawn Friday, flinging most of them into the Atlantic Ocean less than a half-mile off the Turks and Caicos Islands, 125 miles north of Haiti.

"They're very angry and revolted by what happened, because this is a problem that we still can't clarify up until now," Jeanne Bernard Pierre, the director-general of Haiti's National Migration Office, told The Associated Press from the Turks and Caicos, where she met with the detained migrants.

Jean-Robert Lafortune, chairman of the Haitian-American Grassroots Coalition in Miami, said his group may ask the United Nations to investigate.

"We are very concerned that deliberate criminal action may have taken place in the rescue of the Haitian refugee boat," he said.

The British Caribbean territory's government has said it will not comment on the migrants' accusation pending the outcome of investigations, one of which is being carried out by the local government.

Three government experts also arrived from Britain to conduct an independent investigation, said David Stewart, spokesman for the Marine Accident Investigation Branch in Britain.

Turks and Caicos Gov. Richard Tauwhare said Tuesday the vessel capsized while being towed by a police boat in rough seas, contradicting earlier reports by local officials that police arrived only after the migrant boat capsized.

Pierre told the AP she has seen no evidence of a cover-up, but "it's too early to say that we're satisfied with the investigation."

Earlier, Pierre said Haiti would consider the ramming of the migrants boat to be a "criminal" act if the survivors' accounts are found to be true.

The death toll rose to 61 late Tuesday after dozens more bodies were found floating in the ocean. Some had been partially eaten by sharks. More than a dozen migrants are missing and presumed dead.

The decision to tow the overcrowded sloop in stormy seas without giving the migrants life jackets also raised concerns, but lead British investigator Richard Mull said Turks and Caicos police were following procedure.

"The Haitian sloop was on the tow with the Turks and Caicos police boat at the time, as is standard operating procedure, when it capsized," Mull told reporters Tuesday.

Mull said his team interviewed survivors and local police and examined the migrants' wooden sailboat, although he did not say if it had received any damage from a collision. He said a preliminary report should be ready in a few weeks.