BAGHDAD, Iraq (CNN) -- A roadside bomb in northern Iraq killed at least five Iraqi soldiers on Tuesday, an Interior Ministry official said.
The bombing occurred in the Nineveh provincial capital of Mosul, one of the last urban Sunni militia strongholds, during an Iraqi-led operation against al Qaeda in Iraq.
Since launching the offensive on Saturday, Iraqi forces backed by U.S. troops have captured nearly 200 suspects, according to Iraq's Defense Ministry said.
Though most military operations in Iraq have focused on conflicts in Shiite regions, the offensive reflects attempts to root out insurgents in and around Mosul, particularly those loyal to al Qaeda in Iraq.
Elsewhere in the country, Iraqi forces continued to battle Shiite militants despite a temporary cease-fire agreement that was announced at the weekend.
At least 11 people were killed and 20 were wounded in overnight fighting in Sadr City, an Iraqi Interior Ministry official said Tuesday.
In three encounters late Sunday and early Monday, U.S. troops came under fire and shot back, killing three people, the U.S. military said.
The fighting occurred shortly after rival political blocs, including radical Shiite cleric Muqtada al-Sadr's Mehdi Army militia, agreed to a four-day cease-fire in Baghdad's Sadr City.
The truce followed weeks of fighting between Iraqi security forces backed by U.S. troops and Shiite militants. About 1,000 militants and civilians have been killed and more than 2,000 have been wounded since March.
The 14-point agreement was meant to impose the state's authority and security in Sadr City, according to Iraqi government spokesman Ali al-Dabbagh, by ending the militias' armed presence in the sprawling Baghdad slum and clearing the district of roadside bombs and mines.
It was unclear who would abide by the cease-fire. The United States is not party to the discussions.
Following the cease-fire, the government plans to reopen all entrances to Sadr City, allowing necessary aid to flow in and the wounded to be evacuated, said Sheikh Salah al-Obeidi, an al-Sadr spokesman.
Access to the district has been limited during the military operations, and there are shortages of water, food and medical supplies there, according to UNICEF.
Iraqi forces will also be on the district's streets, conducting searches and raids to detain wanted individuals, according to al-Obeidi. He warned that, according to the agreement, the government will punish the security forces if they violated residents' rights in the process.
The Mehdi Army distributed a statement among its members on Saturday instructing them to "hold their positions" until they receive another statement from the Mehdi command.
"When you hear news of agreements or negotiations, and even if news channels and stations broadcast news about a withdrawal or something of the sort, you have to stand firm and not abandon your positions until you hear another statement from the Imam Mehdi Army's command," the statement said.
Spokesmen for the Iraqi government and al-Sadr's Mehdi Army militia announced the four-day cease-fire agreement on Saturday, the same day that a surface-to-air missile was fired at a U.S. helicopter.
The strike was the first of its kind since the fighting erupted in March according to a military spokesman.
In a separate incident Tuesday, attackers in Baghdad fired mortars at two Iraqi government buildings, the Interior Ministry said.
Three mortars slammed into the Interior Ministry building in eastern Baghdad on Tuesday night. There was no word on casualties or damage. A mortar also struck the third floor of the Justice Ministry in central Baghdad and a fire was reported on that floor. No casualties were reported.
CNN's Jomana Karadsheh and Christine Theodorou contributed to this report.