A bomb packed with ball bearings and nails ripped through an Indonesian meat market crowded with holiday shoppers Saturday, killing at least eight people and wounding 45 in a province long been plagued by sectarian violence, officials said.

The attack in the Central Sulawesi town of Palu followed repeated warnings from authorities that the Al Qaeda-linked militant group Jemaah Islamiyah was plotting holiday strikes in the world's most populous Muslim nation.

Brig. Gen. Oegroseno, the provincial police chief, said the bomb went off as people were flocking to the market early Saturday to buy pork for the night's festivities. Palu is about 1,000 miles northeast of Jakarta.

"The explosion was so loud, I couldn't hear for a couple of seconds," said Tega, a resident who lives nearby and uses only one name, like many Indonesians. "I ran out of my house and saw bodies lying around."

Television footage showed police carrying bloodied bodies into ambulances. One man, apparently unhurt, was holding his head in his hands and screaming. Hospital workers and intelligence officials said at least eight people died, and Oegroseno said another 45 were wounded.

The religious affiliations of the dead were not immediately released, but they were believed to be Christians. The market sold only pig and dog meat, both of which are forbidden under Islam.

President Susilo Bambang Yudhoyono condemned the blast, which occurred despite heightened security nationwide. More than 47,000 soldiers and police had been deployed at churches, shopping centers and hotels to try to ward off terror attacks over the Christmas and New Year's holidays.

The country's security minister, Widodo Adisucipto, told reporters the attack was linked to terrorist groups "that have been operating in the country, no other groups," in apparent reference to Jemaah Islamiyah.

The Al Qaeda-linked group wants to establish an Islamic state spanning Indonesia, Malaysia, Singapore and the southern Philippines.

The group has been blamed for a series of deadly bombings in Indonesia since 2000, including two strikes on Bali that together killed 222 people, many of them foreigners. It is also accused in Christmas Eve church bombings five years ago that left 19 dead.

Ninety percent of Indonesia's 210 million people are Muslim, and most people practice a moderate form of the faith. But attacks against Christians have increased in recent years amid a global rise in Islamic radicalism.

Almost half of Sulawesi's population is Christian. The province was the scene of fierce battles between Muslims and Christians in 2001 and 2002 that killed about 1,000 people, and despite a peace deal, violence against Christians has continued.

In October, unidentified assailants beheaded three Christian high school girls in Poso, east of Palu. In May, two bombs in the Christian-majority town of Tentena killed 20 people. Police questioned several suspects in those attacks but have not charged anyone.

Yudhoyono urged police to investigate whether Saturday's bombing was linked to the other attacks, said his spokesman, Andi Mallarangeng. Security officials and former militants have told The Associated Press in recent interviews that Jemaah Islamiyah was involved in the earlier violence.

One Christian clergyman said Saturday he was losing patience.

"Whenever an incident takes place, senior officials ask us to tell the people to remain unprovoked," said Rinaldy Damanik, leader of the Synod Churches of Central Sulawesi. "When will the authorities be able to reveal the barbaric perpetrators in the province?"

Jakarta's police chief, Maj. Gen. Firman Gani, said last week that Jemaah Islamiyah terrorists might use the holidays to retaliate for the November death of bomb-making expert Azahari bin Husin, who was gunned down in a police raid.

On Christmas Eve, bomb squads searched for explosives at churches in the capital, Jakarta, and its satellite cities, where thousands gathered to worship. Security forces also tightly guarded dozens of churches on Sulawesi.