A double bombing on Wednesday injured 25 civilians in the Iraqi city of Karbala ahead of an Islamic holiday, officials said.

One bomb first exploded in a restaurant, drawing onlookers and police, before a homicide bomber on a motorcycle then drove toward the crowd and detonated his explosives, said a provincial police officer and a doctor at al-Hussein General Hospital.

The officials spoke on condition of anonymity because they were not authorized to speak to the media.

The restaurant was strewn with overturned tables and chairs in the aftermath of the blasts. Fragments of broken dishes and slippers littered the bloodstained floor.

"Where is the protection, where is the government?" a distraught woman shouted at Iraqi troops who arrived at the scene.

Karbala, a Shiite holy city, has periodically been targeted by Sunni militants. Overall, violence is down sharply in Iraq.

The four-day holiday of Eid al-Adha begins for Iraq's Sunnis on Friday, while Shiites start the feast on Saturday.