SAN'A, Yemen - Ten key suspects in the bombing of the USS Cole escaped from a Yemeni prison Friday, dealing a major blow to the investigation into the 2000 attack blamed on the al-Qaida terror network.

A massive manhunt is underway for the men, including chief suspect Jamal al-Badawi, who allegedly bought the dinghy packed with explosives and rammed by suicide bombers into the anchored destroyer refueling in the southern Yemeni port of Aden.

Seventeen U.S. sailors were killed in the Oct. 12, 2000, attack.

The fugitives were jailed inside the tightly guarded central intelligence building in Aden.

An Interior Ministry official said on condition of anonymity that the fugitives escaped through a hole in a bathroom wall inside the room they were being detained in.

Earlier, officials close to the investigation said on condition of anonymity that the men smashed a window inside the building and fled.

The different accounts could not immediately be reconciled.

Prison officers gave the men permission to go to the two-story prison complex's courtyard for their daily morning break before they escaped, the officials said.

It was unclear whether the men escaped before or after the daily break and there were no details on whether they were assisted by anyone inside or outside the prison.

Officials said the men may have left Aden for al-Qaida strongholds in the northern province of Shabwah.

A U.S. diplomat refused to comment on the escapes.

A manhunt has been launched and photographs of the escapees have been distributed to police and intelligence agents. Police also searched homes belonging to relatives of the fugitives, the officials said.

The Interior Ministry official told the Yemen state news agency Saba that a reward was being offered for information leading to the escapees' capture. He did not disclose the amount.

The jailbreak likely will have major repercussions for Yemen's security apparatus, which has come under close scrutiny in the wake of the Cole bombing and the Sept. 11, 2001, terrorist attacks in the United States.

The United States has blamed Osama bin Laden's al-Qaida network for the Sept. 11 attacks and the bombing of the Cole.

The 10 fugitives, some of whom are believed to be linked to al-Qaida, were part of a 17-man group arrested following the Cole bombing.

Yemen, a tribal-dominated country on the southern tip of the Arabian Peninsula, committed itself to joining the war on terrorism following the Sept. 11 attacks and has allowed U.S. forces to enter the country and train its military.

In November, a CIA Predator drone fired a missile at a car carrying several suspected al-Qaida operatives, killing Qaed Salim Sinan al-Harethi, bin Laden's top operative in the country.

Yemen is bin Laden's ancestral home and has been an active breeding ground for Islamic militants, who have fought in countries such as Afghanistan and Chechnya.

In December, a suspected Islamic militant shot dead three U.S. Christian missionaries working at a Baptist-run hospital in the remote southern village of Jibla.

Friday's escape was not the first time a top terrorism suspect has busted out of a Yemeni prison.

In June, Walid Abdullah Habib, a Yemeni al-Qaida member from Shabwah, escaped from prison after being arrested earlier in 2002 while trying to enter Yemen illegally.

Al-Qaida supporters in Yemen have claimed responsibility for several bombings that have targeted security officials and government offices during the past few months.

In October, a suicide attack on a French oil tanker off the coast killed a Bulgarian crew member.