KADUNA, Nigeria: A suicide bomber rammed an SUV loaded with explosives into a Catholic church holding Mass on Sunday in northern Nigeria, killing at least seven people and wounding more than 100 others in an attack that sparked reprisal killings in the city, authorities and witnesses said.

As rescuers tried to reach the wounded in the Malali neighborhood of Kaduna, angry youths armed with machetes and clubs beat to death two Muslims passing by the still-smoldering ruins of St. Rita's Catholic church. An Associated Press reporter saw the men's corpses outside the worship hall, as police and soldiers ordered those in the neighborhood of Christians and Muslims to go home before more violence broke out.

The car bombing, the latest high-casualty attack targeting churches, comes as people fear more reprisal killings and religious violence could follow in this city and elsewhere along Nigeria's uneasy religious fault line separating its largely Christian south from its predominantly Muslim north.

The attack happened around 9 a.m. as the reverend of the parish conducted Sunday worship. Witnesses said the suicide bomber plowed his SUV past a gate and a security guard before ramming into the church's wall and detonating the explosives hidden inside the vehicle. The blast left shattered glass and blood across the floors of the church's sanctuary. One of the brown walls of the church caved in and bore scorch marks from the blast.

Rescuers found the bodies of seven worshippers and the suicide bomber after the attack, said Yushau Shuaib, a spokesman for Nigeria's National Emergency Management Agency. Shuaib said more than 100 others suffered injuries in the blast and had been taken to local hospitals.

Kaduna state police commissioner Olufemi Adenaike told journalists at the church that authorities had urged those living in the religiously mixed neighborhood to return home and stay indoors to halt any further revenge attacks. Saidu Adamu, a spokesman for Kaduna state government, said the rest of the city was peaceful.

Reuben Abati, a spokesman for President Goodluck Jonathan, said the nation's leader condemned the attack.

"The persistence of messengers of evil will not prevail over the will of the government and the people to secure peace and safety," Abati said.

No group immediately claimed responsibility for the attack, which comes as the Muslims in the nation are celebrating the end of Eid al-Adha holiday in Nigeria. In recent days, rumors have circulated that the radical Islamist sect known as Boko Haram, which is blamed for hundreds of killings this year alone, might try to launch an attack during the holiday. The sect has demanded the release of all its captive members and has called for strict Shariah law to be implemented across the entire country. However, the group, which speaks to journalists in telephone conference calls at times of its choosing, could not be immediately reached for comment.

The sect has used suicide car bombs against churches in the past, most noticeably a 2011 Christmas Day attack on a Catholic church in Madalla near Nigeria's capital. That attack and assaults elsewhere in the country killed at least 44 people. An unclaimed car bombing on Easter in Kaduna killed at least 38 people on a busy roadway after witnesses say it was turned away from a church.

Christians and Muslims largely live in peace, work together and inter-marry in Nigeria, a nation of more than 160 million people. However, Kaduna, a major city of Nigeria's north that has a large Christian population, has seen hundreds killed in recent years in religious and ethnic violence. More than 2,000 died in Kaduna state as the government moved to enact Islamic Shariah law in 2000. In 2002, rioting over a newspaper article suggesting the Prophet Muhammad would have married a Miss World pageant contestant killed dozens in Kaduna.

After the April 2011 presidential election, protests in Kaduna over Jonathan, a Christian, winning quickly turned into ethnic and religious violence that saw hundreds killed in that state alone. On Oct. 14, gunmen armed with assault rifles attacked a rural Kaduna state village, killing at least 24 people, including worshippers leaving a mosque after prayers before dawn. Officials said the attack likely came from a criminal gang angry over the village killing some of their men. In another attack Sept. 30, gunmen detonated a bomb near an Islamic school in Zaria.

Three church bombings in June claimed by Boko Haram and retaliatory violence after the attacks in Kaduna killed at least 50 people. Some fear the reprisal killings may begin again.

"The northern parts of Nigeria have suffered from so much bloodshed and violence," said Shehu Sani, an activist who runs the Kaduna-based Civil Rights Congress. "We live in a continuous interval of bloodletting. We must not submit to violence or succumb to fear. Intolerance is eroding our liberties and insurgency is destroying our rights."