SANGLA HILL, Pakistan -- The enraged mob had already started to scale the walls of the Catholic compound in Sangla Hill when the Rev. Samson Dilawar hurriedly ushered the nuns, teachers, and 23 teenage students to safety.
The group crammed into a small upstairs room of the convent in eastern Punjab Province. Out on the roof, Dilawar watched in horror as about 1,500 men swarmed across the mission, destroying everything in their path.
The Muslim crowd, incensed by rumors that a Christian had desecrated copies of the Koran, tore open the doors of the Holy Spirit church, smashed the marble altar, and shattered the stained-glass windows. They torched Dilawar's residence and the neighboring St. Anthony's Girls school. Within moments flames were licking the walls and black smoke filled the sky.
An hour later, Dilawar recalled, the mob crashed through the convent door and he retreated into the locked room where the nuns were praying.
''They tried to break the door down, but did not succeed. Otherwise, we could have all been killed," he said Thursday, sitting on a grassy patch outside the vandalized convent.
The violence that swept across Sangla Hill, a market town 140 miles south of the capital, Islamabad, on Nov. 12 has rocked Pakistan's small Christian community.
It has also highlighted the fragile position of religious minorities in this overwhelmingly Muslim country.
Two other churches -- one Presbyterian and the other belonging to the evangelistic Salvation Army movement -- and at least six houses were also torched, in violence that lasted for several hours and that local police were apparently powerless to prevent or combat.
President Pervez Musharraf condemned the attack ''in the strongest terms. Muslims need to show more tolerance towards a smaller, minority community," he told reporters.
But human rights campaigners say the attacks are partly a product of the government's failure to overhaul what many perceive as regressive laws and the reluctance of his Muslim-dominated police to protect minorities.
Under Pakistan's strict blasphemy laws, desecration of the Koran is punishable by life imprisonment, while any proven insult to the name of the prophet Mohammed carries a mandatory death sentence.
The law, which can be invoked on the word of one witness, is frequently misused to settle scores, avoid debts, or rouse violence against religious minorities.
''It is used and misused to spread fear and terror," said Hina Jilani, a lawyer with the Human Rights Commission of Pakistan. ''It's a tool to be used against anyone you are in conflict with."
Both communities agree that the trouble in Sangla Hill started with a blasphemy allegation after a heated gambling session. Two men -- Christian cattle trader Yusuf Masih and a Muslim named Kalu Sunaira -- were playing cards on a patch of open grass near the city sports stadium last Friday morning.
What happened next is in dispute. Muslims allege that Masih became angry after the card game and set fire to a copy of the Koran being stored in a small office belonging to a local Islamic organization.
Christians countered that Sunaira had invented the story to distract attention from a heavy gambling debt he had incurred with his local rival.
Whatever the truth, news of the alleged desecration spread rapidly across the town.
Hours later, after the weekly Friday prayers, Muslim clerics denounced the alleged incident over the loudspeakers.
''They said, 'Come out from your houses for the protection of the Koran and your religion,' " Dilawar recalled.
By 9 p.m. a crowd had gathered outside the Catholic compound and had started to throw stones.
Dilawar called for help. ''I contacted all the officials I knew to request protection. They told me not to worry," he said.
The crowd dispersed but returned about 10:30 the next morning. The small group had swelled into a large mob.
There was evidence of considerable organization. Protesters had arrived from outlying villages, brandishing sticks and hammers.
Witnesses told human rights investigators that some wore green turbans of the type favored by militant Islamists.
After breaking through the walls they torched the buildings using an inflammable orange substance, the traces of which were still apparent on the few unburned walls of the school.
''We've never had anything like this before," the school's headmistress, Sister Anthony Edward, who as part of a tradition within her order, took the names of male saints, said as she stood in front of the charred classrooms. ''I feel broken inside," she said.
Of the school's 450 pupils, at least 90 percent were Muslim, Sister Anthony Edward added.
''People always wanted to bring their children here," she said. ''They appreciate our education."
The Rev. Tajjamal Pervez stood in the blackened ruins of the gutted Presbyterian Church, which was built 103 years ago.
''This was all preplanned," he said bitterly. ''The burning of the Koran was just an excuse to attack."
Police have detained 88 Muslims but have not arrested the town's mayor and a senior councilor, who many Christians allege were the ringleaders behind the attack. Now, Christians say they feel vulnerable to further violence.
''If the police cannot protect us in broad daylight, then what can we expect of them?" said Javed Masih, a nephew of Yusuf Masih, at his ransacked house.
Yusuf Masih remains in jail, but no charges have been pressed, said Arshad Ali, acting chief at Sangla Hill police station. ''He is being held outside of the city because of security," he said.
Both Christians and Muslims in area said they previously enjoyed good relations.
''We even used to attend each other's weddings," said Botta Masih Shindhu, a local Christian leader. ''This is the first time we have seen anything like this in our lifetime."
The leader of the town's mosque, Mufti Muhammad Zulfiqar Rizvi, echoed the sentiment. Christians and Muslims had lived in harmony in the area for generations, he said.
Rizvi denied allegations by Catholic leaders that he had incited the crowd to violence over the mosque loudspeakers on Nov. 12. ''The attackers came from outside this town," he said.
''I tried to stop them. I told them there should be no violence against any religious house. But they would not listen."