BAGHDAD, Iraq  - At least 900 Christian families have fled Mosul in the past week, terrified by a series of killings and threats by Muslim extremists ordering them to convert to Islam or face possible death, officials said Saturday.
 
The attacks may have been prompted by Christian demonstrations ahead of provincial elections, which are to be held by the end of January, the deputy governor of Nineveh province said.

Deputy Gov. Khasro Goran said 13 Christians have been slain in the past two weeks in Mosul, about 260 miles (420 kilometers) north of Baghdad. Fleeing Christians have sought refuge in monasteries and churches and with family members in other towns, an Interior Ministry official said.

The attacks began after hundreds of Christians took to the streets in Mosul and surrounding villages and towns, seeking greater representation on provincial councils, whose members will be chosen in the local elections.

Duraid Mohammed Kashmoula, Nineveh's governor, told The Associated Press that the exodus was "a major displacement."

"Of course, al Qaeda elements are behind this campaign against Christians," Kashmoula told AP.

The Interior Ministry official said the homes of three families were destroyed with explosives Saturday after the occupants left. No injuries were reported.

A week ago, leaflets were distributed in several predominantly Christian neighborhoods, threatening families to "either convert to Islam or pay the jizyah or leave the city or face death," said the Interior Ministry official.

Historically, jizyah is a tax paid by non-Muslims in exchange for protection.

Goran said that a few days after the leaflets were passed out, gunmen set up checkpoints in parts of Mosul, stopping vehicles to inspect identification papers, searching for Christian names or other signs of religious affiliation. Many of the Christians killed were targeted in this way, he said.

Bashir Azoz, 45, told AP he fled his Mosul home after gunmen warned a neighbor to leave or be killed.

"Where is the government and its security forces as these crimes take place every day?" asked Azoz, a carpenter who is staying with his wife and three children in a town about 25 miles (40 kilometers) east of Mosul, according to AP.

The Rev. Bolis Jacob, of Mosul's Mar Afram Church, told AP he couldn't understand the attacks.

"We respect the Islamic religion and the Muslim clerics," he said. "We don't know under what religion's pretexts these terrorists work."

Goran said police have set up security checkpoints in Christian neighborhoods.

In response to the violence, Iraqi Defense Minister Abdul Qader al-Obaidi visited Mosul on Saturday morning, conducting meetings with local authorities and military commanders.

His spokesman, Mohammed al-Askari, said that in addition to ordering more checkpoints in Christian neighborhoods, al-Obaidi ordered more troops deployed, additional security patrols and an increase in aerial surveillance of Christian areas.

Al-Obaidi also ordered more guards for Christian clerics, al-Askari said.