Baghdad, Iraq ? Five bombings in Kirkuk killed 23 bystanders and wounded 76 others Sunday in what appeared to be coordinated attacks on police as well as Kurdish and Sunni Arab politicians in the oil-rich northern city, bringing the day’s toll in Iraq to at least 59 dead.

There has been an upsurge in attacks during recent weeks in Kirkuk, where Kurds and Sunnis have struggled for control of the city’s oil wealth. Late Friday night, a bomb exploded in the Tiseen neighborhood, injuring three people. However, Sunday’s attacks were unusual in their scale and toll.

In the first and deadliest attack, a driver drove a truck loaded with concrete barriers toward the entrance of a police building near Kurdish political offices, shooting at guards as he steered with one hand. Witnesses said that as the guards returned fire, the attacker detonated the bomb, killing himself and 17 others.

Salim Sabbah, 44, threw himself on the ground behind a car as the explosives went off. When he opened his eyes, the normally tranquil street had been transformed into a gory mess of shattered concrete, metal and flesh. Charred bodies were strewn across the road as fires burned in several buildings.

“Why is this happening to us?” Sabbah asked, distraught. He blamed Sunni extremists and foreign fighters. But the diversity of targets during the day made it difficult to determine who might be behind the explosions.

Four subsequent car bombs struck the city on Sunday, including another suicide attack. The second blast hit a Sunni sheik’s office and the third a Sunni mosque. The other attacks targeted Iraqi and American security forces.

Elsewhere in Iraq, 36 people were killed Sunday in assassinations and explosions, or were found dead during the day, authorities said.

Two civilians and three Iraqi police officers were killed in Fallujah in a series of attacks against U.S. and Iraqi security forces involving mortars and several bombs. An American sailor had been killed in the western town Saturday, the U.S. military said in a statement.

A roadside bomb killed two security guards in Baqubah, and in Taji gunmen fired at police patrol, killing two officers, according to Iraqi authorities.

In the capital, two bombs killed two people and injured 12 in separate attacks.

Mohammed Shihab Dulaimi, a Sunni politician and vocal critic of the election which brought the current Shiite Muslim-dominated government to power, was assassinated on an upscale road along the Tigris River after he left the Palestine Hotel following a television interview.

Authorities also recovered the bodies of at least 24 people from Baghdad neighborhoods. Most were found shot, blindfolded and with their hands tied behind their backs. A headless corpse and another body were fished out of the Tigris River near the Sinak Bridge after they had drifted into some reeds along the riverbank.