KIRKUK, Iraq, (Reuters) – A car bomb in a restive region of northern Iraq killed seven people and wounded 61 on Friday, police said, underscoring tensions simmering since an inconclusive March election.

The bomb in a parked car detonated near the home of a provincial official from the Turkoman minority in the town of Tuz Khurmato, southeast of the city of Kirkuk in a region wrestled over by Iraq’s majority Arabs and minority Kurds.

Iraqi police at the scene found a second car packed with rockets and explosives, and were working to defuse it, a police source said.

It was the worst of several attacks on Friday that killed seven other people, including four Iraqi soldiers who died when their patrol left base and was hit by three roadside bombs in Qaim, near Iraq’s western border with Syria, a police source said. Six were wounded.

Overall violence in Iraq has dropped sharply since the all-out sectarian warfare of 2006-7, but shootings and bombings — often targeting the security forces, government officials or former Sunni insurgents who switched sides — are still common.

Sectarian tensions have simmered since an inconclusive election in March that pitted a Sunni-backed cross-sectarian alliance against the country’s major Shi’ite-led political groups. No one won outright, producing a prolonged period of political negotiations over forming a coalition government.

In Baquba, part of Diyala province northeast of Baghdad, a car bomb wounded at least 30 people, hospital sources said. The device exploded near a police captain’s house, wounding six members of his family and shattering windows of nearby homes.

North of Baghdad, in the mainly Sunni city of Samarra, an Iraqi interpreter for U.S. soldiers was shot dead on Thursday by his son and nephew on the orders of a Sunni Islamist insurgent group that considered him a traitor, police said on Friday.

The nephew was arrested along with another of the victim’s sons who let the pair into the house, a police investigator said. The other son escaped. “He had been warned several times by armed groups to stop working with the Americans but he stayed in his job,” said the

investigator, who asked not to be named.

Ansar al-Sunna is affiliated with Sunni Islamist al Qaeda, and has been blamed for a number of deadly bomb blasts, abductions and killings since the 2003 U.S.-led invasion.

Three people were killed and seven wounded on Friday when a rocket fired at a U.S. base landed on houses in Falluja, 50 km (32 miles) west of Baghdad, hospital and police sources said.