Christians are among half a million people who are fleeing their homes after Islamic extremists took control of Mosul, the second largest city in Iraq, earlier this week.
"What we are living and what we have seen over the last two days is horrible and catastrophic. The priory of Mar Behnam and other churches fell into the hands of the rebels this morning ... and now they have come here and entered Qaraqosh five minutes ago, and we are now surrounded and threatened with death ... pray for us," Fr. Najeeb Michaeel, a Dominican priest wrote from Mosul on Tuesday.
BBC News reported that jihadists from the Islamic State of Iraq group, which is affiliated al-Qaeda, overran Mosul and much of the Nineveh province, also taking Baiji, where the country's largest oil refinery is located.
Prime Minister Nouri Maliki said in a television speech that security forces have been placed on "maximum alert." He has asked parliament to declare a state of emergency, which would allow for curfews to be imposed, and call for a "general mobilization of civilians."
One government worker, Umm Karam, said that jihadist flags were flown from the buildings and that the militants told residents over loudspeakers that they had "come to liberate" the city.
"The situation is chaotic inside the city, and there is nobody to help us," Karam said. "We are afraid."
Another resident, Nuri, told AFP: "The army forces threw away their weapons, changed their clothes, abandoned their vehicles and left the city."
Fr. Najeeb said that women and children are among the dead, though an exact number of casualties has not yet been reported.
"Many thousands of armed men from the Islamic Groups of Da'ash (another name for ISIS or ISIL) have attacked the city of Mosul for the last two days. They have assassinated adults and children. The bodies have been left in the streets and in the houses by the hundreds, without pity. The regular forces and the army have also fled the city, along with the governor," the priest noted.
International Christian Concern Regional Manager for the Middle East Todd Daniels said they are "gravely concerned," especially for the already shrinking Christian community in Iraq.
"In a land that has already witnessed more than a million Christians leave over the past decade, we may see the extinction of the entire community. The Iraqi government and the international community must act quickly and decisively to address the threat posed by ISIS and to protect the most vulnerable from additional violence," Daniels stated.
ICC noted that Christians in Iraq have faced great persecution and have been the target of attacks over the decade, causing them to flee and shrink from 1.5 million to an estimated 200,000-400,000.
According to Al Jazeera, ISIL traces its roots to Tawhid and Jihad, a Sunni Muslim group which rose up against the U.S. and Iraq after the fall of dictator Saddam Hussein in 2003.
Abu Musab al-Zarqawi, the leader of Tawhid, declared allegiance to al-Qaeda in 2004, and has inspired suicide bombings and attacks on U.S. and Iraqi targets.
On Tuesday, the U.S. State Department said that it is "deeply concerned" by the developments in Mosul.
"The situation remains extremely serious," Department Spokesperson Jen Psaki said. "The United States stands with the Iraqi people and the people of Ninewa and Anbar now confronting this urgent threat. We will continue to work closely with Iraqi political and security leaders on a holistic approach to diminish ISIL's capacity and ability to operate within Iraq's borders. Our assistance enables Iraq to combat ISIL on the front lines, where hundreds of Iraqi security force personnel have been killed and injured in that fight this year."