Al-Qaeda-linked militants were on Thursday in control of more than half of the Iraqi city of Fallujah and parts of Ramadi, a security official and witnesses said.
"Half of Fallujah is in the hands of ISIL (the Qaeda-linked Islamic State of Iraq and the Levant) group, and the other half is in the control of" armed tribesmen, an interior ministry official told AFP.
A witness in the city west of Baghdad said that militants had set up checkpoints each manned by six to seven people in central and south Fallujah.
"In Ramadi, it is similar -- some areas are controlled by ISIL and other areas are controlled by" tribesmen, the interior ministry official said, referring to the Anbar provincial capital, which lies farther to the west.
An AFP journalist in Ramadi saw dozens of trucks carrying heavily-armed men driving in the city's east, playing songs praising ISIL.
Lyrics included "The Islamic State remains," and "Our State is victorious."
The militants also carried black flags bearing the words "Allah Rassul Mohammed," which are frequently flown by jihadist groups.
Clashes broke out in the Ramadi area on Monday as security forces tore down the country's main Sunni Arab anti-government protest site, and continued for two more days.
On Wednesday, militants in the city sporadically clashed with security forces and torched four police stations, but the clashes had subsided by Thursday, the AFP journalist said.
The violence also spread to Fallujah, where police abandoned most of their positions on Wednesday and militants burned some police stations, officers said.
Iraqi Prime Minister Nuri al-Maliki on Tuesday said that Iraqi soldiers would depart restive cities in Anbar province, but reversed that decision the following day.
Army forces on Thursday remained outside Ramadi.
The removal of the protest camp was a victory of sorts for Maliki, who had long wanted it gone and had termed it a "headquarters for the leadership of Al-Qaeda".
But it has come at a high cost in terms of deteriorating security in Anbar.
And while its closure removed a physical sign of deep-seated grievances among Sunni Arabs, their complaints of being marginalised by the Shiite-led authorities and unfairly targeted by security forces remain unaddressed.