The unrest came amid tight security measures in Baghdad, as Iraq grapples with a protracted surge in bloodshed that has left more than 3,700 people dead so far this year.

Friday's deadly violence struck in the capital and the restive northern province of Nineveh, leaving nine people dead and 22 others wounded, security and medical officials said.

Mortar fire in north Baghdad killed three people, while two men were shot dead in the west of the capital.

The mortar rounds slammed into the Zahra neighborhood adjacent to Kadhimiyah, where tens of thousands of Shiite Muslims prepare to commemorate the martyrdom of a revered figure in Shiite Islam.

For days worshippers from across the country have been walking to Kadhimiyah, site of a shrine dedicated to Imam Musa Kadhim (PBUH), the seventh of 12 revered imams in Shiite Islam, martyred in 799 AD.

The commemoration rituals climax on Saturday and Sunday.

Shiite pilgrims are often targeted by foreign backed terrorist groups. In past years, multiple attacks have been carried out during the Imam Kadhim commemorations.

Due to the heightened threat of attack, the authorities have imposed heavy security measures on the capital, involving the closure of entire roads and barring certain vehicles from the streets.

In Nineveh province, north of the capital, four more people were killed on Friday, including two senior police officers, officials said.

Violence has surged in the past year to its highest level since 2008.

NJF/NJF