Baghdad, Iraq - When Abu Kathim found a note outside his front door next to a large jar of blood, he knew it was the last day he would spend in his home.
"The note said the blood in the jar belonged to the last Shi'ite they had killed and my blood would replace it if I stayed in Taji," said the distressed 37-year-old, referring to a stronghold of Sunni insurgents north of Baghdad.
A member of Iraq's majority Shi'ite community, Abu Kathim had lived in Taji for 25 years.
Tensions between the Shi'ites and minority Sunnis have been running at fever pitch since the February 22 bombing of a Shi'ite shrine in Samarra, north of Taji. The attack pushed Iraq the closest to civil war that it has come since the U.S. invasion.
Fearful of sectarian reprisals that have killed hundreds, Shi'ite and Sunni families have been driven from mixed neighborhoods or towns across the country, resettling in areas where their sect is the dominant one.
Though the sectarian migration is relatively low-scale so far, the process recalls ethnic cleansing in the former Yugoslavia during the Balkan wars.
"This migration is a serious problem and we are increasing our efforts to deal with it, " said Ali al-Adeeb, a senior member of the ruling Shi'ite Alliance. "It is a plan by the terrorists to separate Iraqis and we must make it fail."
In the western Baghdad district of Yarmouk, several displaced Sunnis gathered recently at a mosque to request help from an official in Iraq's largest Sunni party.
Mustafa Abdul-Haq, a Sunni, said Shi'ites in his mixed Baghdad neighborhood of Hurriya had branded his family "terrorists" because his father had grown a long beard reminiscent of those worn by some Sunni militants.
"We left our house on the same day as the Samarra incident when we found out other Sunnis were attacked in the area," Abdul-Haq said. "Our neighbors told us militants fired a rocket-propelled-grenade at the house minutes after we left.."
DRIVEN OUT
Some people have left the capital Baghdadl, a religiously-mixed city of around seven million, and have moved back to their home provinces where their sect is dominant.
But others find nowhere to turn.
In the past week, some homeless families have streamed to the offices of radical Shi'ite cleric and militia leader Moqtada al-Sadr, and to the Sunni Iraqi Islamic Party, where they can find basic accommodation and food.
Records at Sadr's office in the Shi'ite Shula district of Baghdad document the cases of more than 500 displaced Shi'ite families, mostly from areas near Abu Ghraib, a violent town just west of Baghdad that has been a hotbed of Sunni-led insurgency.
"What we have is only the tip of the iceberg. We take their fingerprints and copies of their documents to take a background check to verify their status," said an official at Sadr's office, who refused to give his name because he said he has received death threats.
At the headquarters of the Iraqi Islamic party, at least 43 Sunni families have registered for help after being displaced.
BASIC SUPPORT
Omar al-Jubouri, head of the party's human rights section, said families who arrive receive blankets, food and $35 as temporary support.
"We must not allow outside powers to break up this country," he said. "I call on tribal and religious leaders from Sunni and Shi'ite areas to protect the minorities in their areas."
Some families' desperation to find residence in safer neighborhoods has driven property prices higher, as real-estate agents take advantage of the crisis.
Estate agent Abu Ihsan said demand for homes in the relatively safe district of Mansour in western Baghdad had pushed prices 50 percent higher over the past year.
"Most of the families come from Amriya and Doura, areas that witness security problems," he said in reference to Baghdad neighborhoods with heavy insurgent activity.
A 35-year-old Sunni who gave his name only as Mashadani said he fled the Shi'ite town of Husseiniya, just north of Baghdad, a day after his brother was killed while leaving a Sunni mosque.
"We can never go back to that area because I'm afraid," he said.
Such sectarian distrust is anathema to most Iraqis. While Shi'ites are a majority, there has traditionally been a high level of inter-marriage and many cities, particularly Baghdad, have mixed neighborhoods. That is now changing, dramatically.
"I'm married to a Shi'ite woman and I believe in Muslim unity," said Mashadani. "But my wife now understands that we have to live in Sunni areas from now on."