Iraqi Christians gathered in Baghdad over the weekend to mark Easter, but celebrations were tempered by fears the Islamic State group would eradicate their shrinking community, even as the army launched a U.S.-backed offensive to retake Mosul, their ancestral homeland.

In mid-2014, Christians in Mosul were forced to flee when Islamic State militants seized the northern city and began destroying centuries-old religious sites, ending a presence that once numbered in the tens of thousands and dates back to Christianity's earliest years.

U.S.-backed Iraqi forces launched an offensive against the Islamic State group last week that has been touted as the beginning of a broader campaign to clear areas around Mosul, though progress has been slow.