"Suspected international terrorists have been and are still being captured by the joint forces of the transitional federal government of Somalia and Ethiopia," the Ethiopian Foreign Ministry said in a statement as reported by The New York Times.

After Ethiopian officials acknowledged holding the suspects, who reportedly come from 17 countries, U.S. officials told the Times they had interrogated some of the prisoners in Ethiopian jails.

Human rights groups have accused Ethiopia of violating international law, a charge the Foreign Ministry denied in its statement.

"All legal procedures are being followed, and the suspected terrorists have been allowed to appear before the relevant court of law," the statement said.

The statement said that five suspects from Denmark, Sweden, Tanzania, Sudan and the United Arab Emirates have been freed and 29 other suspects have been cleared by a military court.

The newspaper said many of the suspects were captured in Kenya, sent to Somalia and then transferred secretly to Ethiopian jails.