A suicide attack targeting a police checkpoint outside the capital, Baghdad, has killed at least nine people, to the Associated Press reported.

A police officer said the bomber drove an explosives-laden car into the checkpoint in the town of Suwayrah, killing four policemen and five civilians on Monday, April 21.

The officer said the explosion also wounded 22 people. The town of Suwayrah is located about 40 kilometers (25 miles) south of Baghdad.

A medical official confirmed the causality figures. Both officials spoke on condition of anonymity as they were not authorized to release information, according to the AP.

Iraq is undergoing a surge in attacks since last year, with violence reaching levels unseen since 2008. It has become the Shiite-led government's most serious challenge as the nation prepares to hold parliamentary elections.