Iraq boosted security Monday amid fears of ISIL launching major attacks on Shiite pilgrims flocking to the shrine city of Karbala as further reports emerged of mass killings.
The pilgrims are prime targets for the ISIL jihadists, who have carried out a series of mass executions in recent days, killing scores of members of a tribe in Iraq's western Anbar province.
The jihadists are reported to have slaughtered dozens of members of the Sunni Albu Nimr tribe, which took up arms against them in Anbar.
On Monday, tribal leader Naim al-Kuoud al-Nimrawi told AFP that ISIL "executed 36 people, including four women and three children" on Sunday alone.
Accounts have varied as to the number and timings of the executions, but sources have spoken of more than 200 people murdered in recent days.
A police officer and an official gave figures of more than 200 to 258 people killed, while Iraq's human rights ministry put the toll at 322 and a tribal leader said 381 were executed.
The mass killings appear aimed at discouraging resistance from powerful local tribes in Anbar, where ISIL overran large areas in June as pro-government forces suffered a string of setbacks.
Hundreds of thousands of pilgrims are expected in Karbala for the Tuesday peak of Ashoura marking the death of Imam Hussein, one of Shiite's most revered figures.
At least 19 people were killed in bomb blasts targeting Shiites in Baghdad Sunday claimed by ISIL, and security forces were on alert for further attacks.
Karbala deputy governor Jassem al-Fatlawi told AFP "hundreds of thousands of Iraqi pilgrims" and 65,000 others from 20 different countries have thronged Karbala.
Pilgrims have been targeted during Ashoura before, but this year they face even greater danger after the ISIL lightning offensive in June.
Like other Sunni extremists, ISIL considers Shiites heretics.
Authorities have deployed thousands of security personnel and allied militiamen to protect the pilgrims, in a major test for the new government headed by Prime Minister Haidar al-Abadi.
"The security plan is fully in effect and the security forces are on a state of high alert," an Iraqi police colonel told AFP, speaking on condition of anonymity.
Police were deployed throughout Shiite districts of Baghdad and security forces are guarding the 100-kilometre (60-mile) route from the capital to Karbala.
More than 26,000 members of the security forces were deployed in Karbala itself, backed by helicopters providing air support and monitoring desert areas, army Staff Lieutenant General Othman al-Ghanimi told reporters.
Police used X-ray trucks to scan vehicles as sniffer dogs monitored arrivals and some 1,500 policewomen checked female pilgrims.
The Sunni extremist ISIL has declared a "caliphate" in parts of Iraq and neighboring Syria under its control, imposing its harsh interpretation of Islamic law and committing widespread atrocities.
There are fears that Anbar province, stretching from Iraq's borders with Jordan and Saudi Arabia to the western approach to Baghdad, could fall entirely.
A U.S.-led coalition of Western and Arab nations has carried out a wave of airstrikes on ISIL positions in Iraq and Syria, with Canadian CF-18s conducting their first raids Sunday around the Iraqi city of Fallujah.
The Pentagon said its aircraft carried out five strikes Sunday and Monday around Syria and nine in Iraq.
Singapore said Monday it would provide military support including a Boeing KC-135R Stratotanker for air-to-air refuelling.
Kurdish militia have been holding off an ISIL offensive on the Syrian border town of Kobani for nearly seven weeks and have been reinforced by about 150 Iraqi Kurdish peshmerga fighters with heavy weapons.
Kobani just across the border from Turkey has become both a key symbol of resistance to the ISIL advance and a rallying point for the jihadist cause.
Over the weekend, the peshmerga targeted ISIL positions with rockets, according to the People's Protection Units (YPG), the Syrian Kurdish militia defending the town.
The Syrian Observatory for Human Rights, a Britain-based monitoring group, reported sporadic clashes at the town.
It said the coalition carried out at least four strikes near Kobani early Monday and hit a convoy headed to the town from ISIL-controlled Minbej.
The Observatory said 20 jihadists were killed in coalition strikes in Kobani and elsewhere, and that at least four ISIL militants and two YPG fighters died Sunday.
It also said ISIL beheaded eight Syrian rebels it captured in the eastern province of Deir Ezzor and hung their bodies on makeshift crucifixes.
