At least five people were killed and six more wounded after a series of explosives-packed cars and suicide bombs were detonated in the western Iraqi city of Ramadi on Sunday.
Four car bombs had targeted a mosque and a police building in the city, AFP news agency reports. The bombs were followed by two suicide bomb blasts inside the police building.
Security forces had cordoned off the police building, which also holds several al Qaeda suspects in a jail, officials said.
“Police and army are surrounding the building. There is no exchange of fire, but the security forces are studying storming the building and saving the hostages,” the police official said.
Ramadi, capital of the mainly Sunni Muslim Anbar province, witnessed some of the worst violence during the height of the war that followed the 2003 U.S.-led invasion. It was the heart of a Sunni Islamist insurgency tied to al-Qaeda.
The initial suicide bomb blast killed five people but it was not clear how many possible hostages were inside, one police official at the scene said.
Violence in Iraq had ebbed since the height of sectarian slaughter in 2006-2007 when thousands were killed in attacks between Shiite and Sunni groups. But the withdrawal of the last American troops in December has fanned worries of a spike in violence.
The attack in Ramadi came a day after a suicide bomber disguised as a policeman killed at least 50 people in an attack that targeted Shiite Muslim pilgrims passing through a checkpoint in Iraq’s southern city of Basra.
“A terrorist wearing a police uniform and carrying fake police I.D. managed to reach a police checkpoint and blew himself up among police and pilgrims,” said a police official at the scene of the bombing on Saturday.
Women and children were among the casualties, he said, but did not give further details.
The attacker, who had been distributing food to pilgrims walking to the Khutwa Imam Ali, a site on the outskirts of Basra venerated by believers for its associations with one of the key figures of their faith, blew himself up near a police checkpoint.
Arbaeen has been a frequent target of militants since the U.S.-led invasion that ousted Sunni dictator Saddam Hussein.
Scores of people have been killed in attacks on pilgrims in the last few weeks, including a suicide bombing which killed at least 70 people.
Many of the attacks on pilgrims have used methods such as suicide bombings that are the signature of Iraq’s al-Qaeda affiliate.
Attacks targeting Shiites have also killed dozens of people since Shiite Prime Minister Nuri al-Maliki’s government issued an arrest warrant for a Sunni vice president, triggering a political crisis that risks scuttling a power-sharing agreement.