Baghdad (CNN) -- A police officer was killed and three others wounded when hundreds of demonstrators protested in the Iraqi town of Halabja over lack of basic services, corruption and unemployment, the town's mayor said Thursday.
Some of the protesters shot at police while they were trying to force their way inside some government institutions, including the city council building, Mayor Goran Adham told CNN. Iraqi security forces detained a number of people, he said.
On Tuesday, hundreds protesting for the same reasons started throwing stones at Iraqi police, the mayor said, wounding 43 police officers.
Halabja is located about 84 kilometers (52 miles) southeast of Sulaimaniya in Iraq's Kurdish region. Sulaimaniya is about 260 kilometers (161 miles) north of Baghdad.
Meanwhile, Iraqi Prime Minister Nuri al-Maliki urged citizens Thursday not to participate in massive planned demonstrations in Baghdad on Friday, saying there is a plot by Baathists -- former members of Saddam Hussein's regime -- and terrorists to infiltrate them. The Baathists and terrorists want to take advantage of the demonstrations to create chaos in the country, al-Maliki said.
"I ask Iraqi people not to participate in tomorrow's demonstrations in order to abort plans of the enemies of freedom and democracy and because it is suspicious," he said.
Iraq's top Shiite religious leaders, including clerics Ali al-Sistani, Muqtada al-Sadr, have urged that the Friday demonstrations be delayed.
On Wednesday, al-Sadr submitted an initiative for the Iraqi people to hold a one-week referendum on the basic services issue and postpone the demonstrations for six months.
"If the government does respond and improve the services for more than six months then Iraqi people can hold peaceful demonstrations and Muqtada al-Sadr will support and adopt these demonstrations," said al-Sadr senior aide Sheik Hazem al-Araji , who read the cleric's statement on Iraqiya state television on Wednesday.
Iraqi security forces have been on full alert since Monday and more Iraqi troops have been deployed to the streets of Baghdad ahead of the demonstration on Friday, officials with Iraqi security forces tell CNN on condition of anonymity because of security concerns.
At about 2 a.m. Wednesday, dozens of gunmen raided the offices of the Journalistic Freedoms Observatory. an Iraqi press watchdog, in the Karrada district of central Baghdad. The organization's chairman, Hadi Jalow Marai, told CNN that furniture was destroyed and computers, documents and other items were stolen.
A guard who was in the building during the raid reported that more than 30 gunmen, some of them wearing military uniforms, and others dressed in black broke the locks on the doors, Marai said. Items missing include digital cameras, video cameras, several mobile phones, bulletproof vests and helmets, he said.
"We don't want to accuse any group or party (of being) behind this raid," but the group demands that the Iraqi government conduct an investigation, he said.
However, observatory officials told CNN on condition of anonymity because of security concerns that the Iraqi security forces are thought to be behind the raid because the government believes the Journalistic Freedoms Observatory is behind the planned Friday demonstrations.
Since early February, dozens of thousands of protesters have participated in a series of demonstrations across the country, apparently inspired by popular uprisings in Egypt and Tunisia. Their protests are against corruption, restrictions on freedom of expression, unemployment and poor government services.
The Iraqi government was formed in December, nine months after an inconclusive national election. This is the second elected government in the nearly eight years after a U.S.-led invasion toppled Hussein.
At the end of 2011, the United States is set to withdraw all of its troops from Iraq as part of a bilateral agreement with the Baghdad government. It is too soon to predict whether that will happen or whether the United States and Iraq will negotiate an agreement to keep some U.S. soldiers there after year's end.