The Shia faithful in Baghad and Kirkuk in Iraq were targeted by suicide bombers on Friday, leaving at least 15 dead, the BBC reported.
According to reports by officials at the scene, the bombs went off within an hour of each other and were timed to explode as Shia worshippers were leaving the mosques following Friday prayers.
Dozens of others were left wounded by the bombings.
Attacks of this nature have swept across Iraq in recent months as sectarian tensions continue to rise. The Sunni minority are considered the most likely to carry out such bombings.
Iraq's Shia-led government has been accused of targeting its Sunni minority unfairly using new anti-terror legislation against them. The northern, predominently Kurdish, city of Kirkuk has also been the scene of violent attacks as the regional semi-autonomous government battles with Baghdad for control of oil contracts.