Our correspondent said US military headquarters and a patrol in the town of Fallujah came under rocket-propelled grenade attack overnight on Wednesday.
Swarms of occupation forces raided the town, west of Baghdad, in search of the assailants.
There were no reports of casualties. Fallujah has been tense ever since the incident in which US soldiers opened fire on civilians demonstrating against the occupation, killing 16 people.
In Ramadi, two explosions were heard followed by a ten-minute exchange of fire. Our correspondent said flares were fired in the northern, southern and western areas of the flashpoint town.
There were no other details on the explosions. A curfew was imposed on the town overnight.
There is rising discontent among
Iraqis towards their occupiers
In the northern city of Arbil about 100 university professors demonstrated to protest a major cut in their salaries.
The academics from Arbil's Salahaddin University said the US occupation troops were paying them around 75 percent less than the Kurdish parties controlling the region did before Hussein was ousted.
Arbil is the stronghold of Massoud Barzani's Kurdistan Democratic Party (KDP), which shared control of Iraqi Kurdistan with Jalal Talabani's Patriotic Union of Kurdistan (PUK), since the end of the 1991 Gulf War.
'Wanted' Iraqis detained
Former Iraqi Interior
In other developments, two people on Washington’s list of 55 most-wanted Iraqis are in US custody.
The US Central Command said Mizban Khadr al-Hadi, a former high-ranking regional Baath party leader, turned himself in to American troops in Baghdad on Tuesday.
He was number 23 on the Pentagon’s “deck of cards”, featuring most wanted former Iraqi government officials.
Former Interior Minister, Mahmoud Dhiyab al-Ahmad, who is number 29 on the list, was captured in an undisclosed location in Baghdad.
The detentions bring to 34 the number of senior officials on Washington’s list who are in US custody.