At least 12 people were killed and 53 wounded today when a suicide truck bomb exploded outside the Iraqi Interior Ministry in the Kurdish city of Irbil.
Kurdish television showed footage of a building that had been almost completely destroyed.
Rubble lay in piles and long metal beams were twisted. Rescue workers reached into the wreckage to pull out one of the victims of the blast. Windows were blown out down the street and wreckage was scattered nearly 100 yards away.
Hamza Ahmed, a spokesman for the Irbil governor's office, said the blast targeted the Interior Ministry. He said the casualties included police and civilians.
Irbil, 230 miles north of Baghdad, is the capital of the Iraq's Kurdistan region, which has been relatively calm, despite the violence in much of the rest of Iraq.
The Interior Ministry, the apparent target of the blast, is next to the parliament for the Kurdish Autonomous region of northern Iraq.
The latest bombing came as US Vice President Dick Cheney sought to encourage reconciliation among rival Iraqi factions today in an unannounced visit to Baghdad.
He emphasised that the current US military build-up alone was not an end to the conflict.
Mr Cheney made Iraq the first stop of a week-long trip to the Middle East aimed at redoubling efforts to end divisive infighting among Iraq's ethnic factions.
He received a first-hand briefing on conditions from Gen David Petraeus, the top US commander in Iraq, and the new US ambassador there, Ryan Crocker.