Violence has surged to a level not seen since 2008, when Iraq was just emerging from a brutal period of sectarian killings in which tens of thousands died.
And shifting parts of Anbar provincial capital Ramadi and all of the city of Fallujah, to its east, have been held by anti-government fighters for more than eight weeks.
Sabah Noori, spokesman for Iraq's Counter-Terrorism Service, said its forces had killed 52 jihadist militants in fighting since yesterday in Ramadi.
The dead included foreign fighters, he said, adding that operations to retake some areas of the city were still ongoing.
More From This Section
The crisis in Anbar province erupted in late December when security forces dismantled Iraq's main Sunni Arab anti-government protest camp just outside Ramadi.
More than 370,000 people may have been displaced by violence in Anbar, according to the United Nations.
Violence in other areas of Iraq killed 10 people today.
The source of the fire was not immediately clear.
In Baghdad, a bomb exploded in a market, killing one person and wounding five, while gunmen shot dead a policeman in Abu Ghraib, west of the capital.
And attacks in the northern province of Nineveh -- one of the most dangerous areas of the country -- killed four people, including a lawyer and a policeman.
Iraq is suffering a year-long surge in violence driven by widespread discontent among the minority Sunni Arab community, and by the bloody civil war in neighbouring Syria.