A truck bomb ripped through a busy market north of the Iraqi capital Thursday, killing at least 17 people and wounding dozens of others.
The attack in Samarra - a largely Sunni Muslim city about 100 kilometers north of Baghdad - and a separate bombing that killed at least six in a Baghdad suburb - are the latest in a surge of apparent sectarian violence this year.
The Thursday evening bombing hit the Samarra market, the city's largest grocery shopping area, as shoppers sought to take advantage of reduced prices on surplus stock before closing.
At least 75 people were killed and more than 200 others wounded Wednesday in a wave of bombings and shootings across the country.
Analysts say the country appears to be sliding back toward civil war, as Sunni militants linked to al-Qaida mount increasingly deadly attacks on Shi'ite targets on a near daily basis.
The United Nations says nearly 4,000 people have died this year, most of them since April, when forces of the Shi'ite-led government cracked down on a Sunni protest encampment north of Baghdad.