At least 24 civilians were killed on Saturday in a car bombing claimed by the Islamic State extremist militia in the Iraqi capital Baghdad.
The blast took place near a marketplace in the neighbourhood of Nahrawn in south-eastern Baghdad. Police said 33 people, including three security personnel, were wounded.
The bomb went off on a road used by Shiite pilgrims on their way to the holy shrine of eighth-century Imam al-Khadim in northern Baghdad for an annual ceremony.
Police said all the dead were civilians, but could not confirm if they included pilgrims.
A statement in the name of Islamic State said the attack was carried out using a truck packed with three tons of explosives.
A suicide bomber allegedly drove the truck into a crowd of Shiite pilgrims, according to the statement that was circulated by Islamic State supporters on social media.
The statement could not be verified.
The Islamic State radical Sunni militia regards Shiites as heretics.
The extremist group has a record of launching deadly attacks against Shiite communities in Iraq and elsewhere.
The bombing comes as Iraq is also grappling with a political crisis over reforms, and Prime Minister Haider al-Abadi is trying to form a new government of independent technocrats.
Major political blocs in parliament have blocked the move in recent weeks.
Iraqi governments have been formed along political and sectarian lines since the US-led 2003 invasion that deposed Saddam Hussein.
Critics say the system contributes to corruption.
Al-Abadi, a Shiite politician, has warned that the current crisis can hamper the country's US-backed fight against Islamic State, which controls key areas in Iraq's Sunni heartland.