Updated

BAGHDAD -- A suicide bomber blew himself up Thursday evening in a crowd of people rushing to help victims from a blast minutes earlier, killing eight policemen and wounding 20 bystanders, authorities said.

The first explosion came around 6 p.m. in downtown Ramadi, the Sunni-dominated capital of Anbar province 70 miles west of Baghdad, said local council chairman Jasim al-Halbusi.

Minutes later, the suicide bomber joined the crowd of people trying to help the wounded and detonated his explosives-packed vest. Al-Halbusi said the suicide bomber was wearing a military uniform.

Eight policemen were killed and 20 people were wounded in the double-bombing, according to an official at Ramadi hospital, where the victims were taken. He spoke on condition of anonymity because he was not allowed to release the information.

A third blast near the hospital caused no casualties, al-Halbusi said.

Ramadi has been a frequent target for insurgents, who have attacked the government headquarters four times over the last year alone, including a bombing in which the governor lost a leg. The city was a hotbed of the insurgency at the peak of the Iraqi war just a few years ago.

In Baghdad, a roadside bomb Thursday morning killed two Iraqi civilians in a mainly Shiite area, police and health officials said. A police official said four people were wounded, including two traffic policemen.

A doctor at the hospital where the wounded were taken confirmed the casualties.

Both officials spoke on condition of anonymity because they were not authorized to release information.

Violence in Iraq has ebbed since 2008 after a series of U.S.-backed offensives, but insurgents are still able to launch attacks.