A motorcycle rigged with explosives went off near a Shiite mosque south of the capital Baghdad, killing three people and wounding 34, Iraqi security officials said Saturday.
The officials said the blast happened the previous evening on a commercial street in the village of Mussayyib. They spoke on condition of anonymity in line with regulations.
ISIS group claimed responsibility for the attack, saying it targeted "gatherings of Shiites" near a Shiite mosque.
Iraq declared victory against ISIS in late 2017, but the group continues to carry out attacks through sleeper cells, particularly in the country's north.
Iraq's military announced it started a new operation early Saturday targeting ISIS hideouts and sleeper cells in western Anbar province.
The military said the operation aims to "search and clear" wide desert areas in the province that borders Saudi Arabia, Jordan and Syria.