Islamic State militants have captured the main government compound in Ramadi after fierce clashes with Iraqi security forces, officials said.
The city's mayor Dalaf al-Kubaisi said the militants raised the black flag of IS over the area after troops were forced to withdraw from the compound, which houses most of the city's government offices.
He says the IS militants are now attacking the Anbar Operation Command, the military headquarters for the province.
US troops saw some of the heaviest fighting of the eight-year Iraq intervention in Anbar, and Ramadi was a major insurgent stronghold.
The IS assault on the government compound began with three near-simultaneous suicide car bombings that killed 10 police and wounded seven others
Mr al-Kubaisi sa id at least 10 police were killed in the fighting and dozens of other security forces were wounded. He said IS militants killed several captured policemen and army officers in the city, where most civilians have fled.
IS captured the nearby city of Fallujah and parts of Ramadi in January last year, months before its main sweep across northern and western Iraq.
Dozens of families were forced to flee their homes in the area after the new assault, said Athal al-Fahdawi, an Anbar councillor.
The head of Anbar's provincial council, Sabah Karhout, appealed to the central government in Baghdad to send reinforcements and urged the US-led coalition to increase air strikes against the militants in Ramadi.
"The city is undergoing vicious attack ... and we are in dire need of any kind of assistance," Mr Karhout said.