Gunmen in cars opened fire on Friday in Baghdad's Khilani Square leaving at least 15 people dead and 60 wounded, Iraqi security and medical officials said. At least two of the dead were policemen.

Protesters fearing for their lives ran from the plaza to nearby Tahrir Square and mosques to take cover. It wasn't immediately clear who did the shooting.

The attack came as anti-government demonstrators occupied parts of Jumhuriya, Sinak and Ahar bridges in a standoff with security forces. All the bridges lead to or near the heavily-fortified Green Zone, the seat of Iraq's government.

"We are under live fire now with electric power cut, the wounded and martyrs are here and the bullets were fired in Sinak Bridge," said one protester, who did not give their name for fear of retaliation.

The attack came a day after a string of suspicious stabbing incidents targeting demonstrators left at least 13 wounded in Baghdad's Tahrir Square, the epicenter of Iraq's leaderless protest movement.

Those attacks by unknown perpetrators occurred as demonstrators supporting political parties and Iran-backed militias withdrew from the Square . The incidents on Thursday fueled paranoia among protesters, who immediately implemented self security measures to uncover saboteurs within the square.