Four bombs have exploded in Iraq, killing 42 people and wounding more than 200.
Two truck bombs exploded in a Shia village near the northern city of Mosul, killing 30 people and wounding155.
In Baghdad, a car bomb and a roadside bomb targeting labourers queuing for work killed seven people in mostly Shi'ite areas of the capital's southwest, a hospital source said. A later car bomb in the same area killed another two people.
In other Baghdad attacks, roadside bombs and a bomb stuck to a bus killed three people and wounded 34.
The attacks are the latest in a series of several major incidents since US combat troops withdrew from urban centres in June.
Bombings and shootings are reported almost daily in and around Mosul, capital of Nineveh province, where disputes between Arabs and Kurds threaten to split the region and inflame tensions that could threaten Iraq's long-term stability.
The violence raises doubts about the readiness of Iraq's security forces, rebuilt from scratch after the 2003 US-led invasion, to cope alone, and also bolsters fears of a resurgence of sectarian slaughter between Sunnis and Shias.
Bloodshed has abated in the last 18 months, but before that dozens of bodies were dumped on Baghdad's streets each day and morgues overflowed with victims of the violence.
Insurgents have been able to hide in the remote, mountainous areas around Mosul.
Last week, a string of bombings targeting Shia Muslims in Baghdad and northern Iraq killed 44 people. Sunni Islamist militants such as al-Qaeda, who consider Shias heretics, are often blamed.
US Defense Secretary Robert Gates said in a visit to Iraq last month there was some chance of a "modest acceleration" of a US troop withdrawal if security improves.
National elections in January will be a key test for Iraq's fledgling democracy and its security forces.
Agencies