PORT-AU-PRINCE: Nine US citizens were being held in Haiti Sunday after being arrested for allegedly trying to take 33 Haitian children out of the country, according to Haiti's Culture and Communications Minister Marie Laurence Jocelyn Lassegue.

Border police "saw a bus with a lot of children. Thirty-three children. When asked about the children's documents, they had no documents," Lassegue told reporters here.

"They are now in the hands of justice. There are nine people and they are Americans," she said.

Official here earlier had said that police arrested 10 Americans who had tried to leave the country with 31 children, but on Sunday revised those figures.

The children are between two months and 14 years old, Lassegue said, and are now being held in a care center, but did not say where.

A police official however said the children had been transferred to a facility north of the city, in Croix des Bouquets.

Lassegue would not comment on the reason the Americans were being held or any possible court appearance.

A spokesperson at the US embassy here was not immediately available for comment.

The Americans, members of a US Christian ministry group, are being held at the Judicial Police headquarters near Port-au-Prince's international airport -- the site of the relocated national government.

Haitian authorities have tightened travel restrictions for children in the country, and said the prime minister for the time being will have to sign off on every minor's departure abroad.

Officials here have voiced fears that child traffickers could take advantage of the chaos after Haiti's massive January 12 quake to slip out of the country with children in illegal adoption schemes.