BAGHDAD — The message played over loudspeakers gave the Christians of Iraq’s second-largest city until midday Saturday to make a choice: convert to Islam, pay a tax, or face death.
By the time the deadline imposed by the Islamic State extremist group expired, the vast majority of Christians in Mosul had made their decision. They fled.
They clambered into cars — children, parents, grandparents — and headed for the largely autonomous Kurdish region of northern Iraq or other areas protected by the Kurdish security forces.
Their departure marks the latest — and perhaps final — exodus of Christians from the city, emptying out communities that date back to the first centuries of Christianity, including Chaldean, Assyrian, and Armenian churches.
Iraq was home to an estimated 1 million Christians before the 2003 US-led invasion that ousted Saddam Hussein.
Since then, militants have frequently targeted Christians across the country, bombing their churches and killing clergymen. Under such pressures, many Christians have left the country. Church officials now put the community at around 450,000.
Most of Mosul’s remaining Christians fled when the Islamic State group and an array of other Sunni militants captured the city June 10 — the opening move in the insurgents’ blitz across northern and western Iraq. As a religious minority, Christians were wary of how they would be treated by hard-line Islamic militants.
For those Christians who remained in the city, the order first made over loudspeakers on Thursday and later in leaflets passed out on the streets made clear their status under the extremist group’s rule.
‘‘When the Islamic State people took over Mosul weeks ago, they were nice to us at first and they used to knock our door and tell us that they mean no harm to the Christians in Mosul and they even gave us a mobile number just in case we are offended by anybody,’’ Sahir Yahya, a Christian and government employee from Mosul, said Saturday. ‘‘This changed two days ago. The Islamic State people revealed their true savage nature and intention.’’
Yahya fled with her husband and two sons Friday morning to the town of Qaraqoush, where they have found temporary lodging at a monastery.
In Mosul, the Islamic State group has gradually imposed its strict interpretation of Sharia law. The militants banned alcohol and painted over street advertisements showing women’s faces, for example, but have held off on strict punishments.
More recently, the group began seizing the houses of Christian and Shi’ite Muslim families who fled Mosul and gave some of them to Sunni families uprooted from other areas, residents said.
Still, the edict calling on Christians to convert, pay a tax, or face death took many in the community by surprise.
‘‘I went to the Islamic State religious court to make sure that the statement is authentic, and the man there told me that I should leave my house, car, money, and properties behind,’’ said Maan Abou, a 45-year-old retired army officer.
On Friday, Abou left his home and washing machine repair shop in Mosul behind and headed for Kirkuk with his wife and four children, as well his parents and his sister’s family.
‘‘All that I want is to return to the city that I grew up in and that I still have nice memories of,” he said. “I have strong faith that we will return sooner or later because the cruel rule of Islamic State will not last forever.”
On Saturday, a series of bombings, including three over a span of less than 10 minutes, killed at least 27 people, police said. The attacks hit the neighborhoods of Abu Dashir, Baiyaa, Jihad, and Khazimiyah.