BEIRUT, Lebanon (AP) - Hezbollah said Saturday it was withdrawing its gunmen from Beirut neighborhoods seized in sectarian clashes after the army ordered its troops to establish security and called on fighters to clear the streets.

But while tensions in the capital appeared to be defusing, violence spread to other parts of the country.

At least 12 people were killed and 20 wounded when pro- and anti-government groups fought in a remote region of northern Lebanon, Lebanese security and hospital officials said.

It was the heaviest toll for a single clash since sectarian fighting began on Wednesday. At least 37 people have been killed in four days of clashes.

Iranian-backed Hezbollah and its allies seized large swaths of Muslim west Beirut Friday, demonstrating their military might in a power struggle with the U.S.-backed government. It was the worst sectarian violence since Lebanon's 1975-1990 civil war.

The clashes broke out after the government challenged Hezbollah by declaring its private telephone network illegal and saying it would remove the chief of airport security for suspected ties to Shiite militant group.

Hezbollah's leader Hassan Nasrallah said the decisions amounted to a declaration of war and he demanded they be revoked. His Shiite forces then overran Beirut neighborhoods, routing Sunni supporters of the government.

Western-backed Prime Minister Fuad Saniora, in his first public statement since the sectarian violence erupted, said Lebanon can no longer tolerate Hezbollah having weapons. He called on the army to restore law and order and remove gunmen from the streets. He also accused Hezbollah of staging a coup and besieging the capital.

The dream of democracy in Lebanon has been dealt "a poisonous stab by the armed coup carried out by Hezbollah and its allies," he said.

After Saniora's speech, the army called for gunmen to withdraw from the streets of Beirut and reopen blocked roads. It ordered army units "to continue to take measures on the ground to establish security and spread state authority and arrest the violators."

Saniora said he would leave it up to the army to resolve the fight over the airport security chief and the Hezbollah telephone network.

The army offered Hezbollah a compromise, saying the airport security chief would not be sacked and recommending the government revoke its decision to declare the communications network illegal.

The army has largely stayed out of the fighting, fearing its forces could break apart on sectarian lines as they did during the civil war. The army command is respected by Hezbollah.

An opposition statement said its forces will withdraw all their gunmen from Beirut in compliance with the army request.

But it said a "civil disobedience" campaign will continue until its demands are met. The statement did not say whether Hezbollah forces would remove roadblocks around Beirut including one cutting off access to the airport since Wednesday.

Muslim west Beirut appeared mostly calm a day after Hezbollah and its allies seized large parts of the area. Most Hezbollah gunmen had pulled out, leaving small bands of their Shiite Amal allies to patrol the streets.

In other parts of the country, however, violence appeared to be intensifying.

Fighters loyal to Sunni parliament majority leader Saad Hariri and the government battled the Syrian Social Nationalist Party, a secular pro-Syrian group allied with Hezbollah. The clash broke out in the town of Halba in a remote Sunni region of northernmost Lebanon.

At least 12 gunmen were killed and 20 wounded, Lebanese security and hospital officials said. The pro-government fighters stormed the office of the SSNP and set it ablaze after the gunbattle. Nine of the dead were SSNP and three were government loyalists, the security officials said.

Both they and the hospital officials spoke on customary condition of anonymity because they were not authorized to speak to the media.

In a mountain town east of Beirut, Hezbollah accused a pro-government Druse group of kidnapping three of its members and killing two of them.

Eight people were killed near the town of Aley late Friday in clashes between government supporters and opponents. Another civilian died in the clashes in the southern city of Sidon.

Earlier Saturday in Tarik Jadideh, a Sunni Muslim neighborhood of Beirut, a Shiite shop owner opened fire on Sunnis in a funeral procession as they passed his store chanting insults at Shiite Hezbollah leaders. Troops captured the gunman, who killed two and injured six, police and witnesses said.

After the attack angry people stormed the alleged gunman's shop and set it ablaze. They attacked another shop with stones, shattering its glass.

Tarik Jadideh is a stronghold of Sunni supporters of Saad Hariri, the parliamentary majority leader and son of assassinated former premier Rafik Hariri.

Elsewhere in the capital, residents ventured out in small numbers to streets held by both Lebanese troops and lingering bands of Shiite gunmen.