KurdistanObserver.com

BAGHDAD, Iraq, Friday, Nov. 12 - The sounds of automatic rifles firing, rocket-propelled grenades exploding and helicopters buzzing through the sky reverberated through the northern city of Mosul on Thursday, with a ferocity that took some residents back to the early days of the invasion of Iraq.

Halla Mukdad, a professor of economics and business administration at Mosul University, said she could not leave her home. "The armed people are right outside our house door," she said.

In the spring of 2003, it was American armor rolling in. Now, it was insurgents - storming police stations and stealing guns, ammunition and body armor; setting fire to buildings and police cars; and even making off with a generator.

Later, gun battles with American and Iraqi forces broke out at the five Tigris River bridges the insurgents had seized. Kiowa helicopters swooped above the palm trees and sand-colored buildings, surveying the streets.

Mosul, the third largest city in Iraq, has been torn by deadly violence throughout the occupation, with car bombings and assassinations becoming almost a routine part of daily life.

But the assaults have grown so incendiary over the last two days, the Stryker Brigade, the light-armored mobile unit charged with controlling the region, is pulling its battalion out of the Falluja operation to send it north. Three Stryker battalions are already in the Mosul area.

American commanders have said insurgent leaders probably fled from Falluja in the days or weeks before the offensive there and may be organizing the wave of counterattacks roiling central and northern Iraq. Mosul has seen the toughest fighting outside Falluja.

In the morning, as the attacks on the police stations began, 13 sedans full of jihadists pulled up to the police academy. They opened fire with rifles and rocket-propelled grenades. When they realized no one was inside, they broke open the doors and began looting.

The same thing happened at the Zuhoor police station, where the generator was carted away.

One group laid siege to the headquarters of the Patriotic Union of Kurdistan, one of the country's main Kurdish political parties. The building once housed the local offices of the Baath Party of Saddam Hussein and was set back from the residential areas. A half-dozen Kurdish militiamen managed to hold off the attackers with heavy machine guns.

Near Mosul University, insurgents chased down two vehicles used by the Iraqi National Guard and set fire to them.

The governor of Nineveh Province had imposed a round-the-clock curfew starting Wednesday, when battles first flared. Few people were out on the streets on Thursday. But they seemed to be staying indoors more out of fear of the fighting than out of obedience to authority.

"I've got to stay home because of the events," said Sheiban Sabir, a salesman in a pest extermination company. "It's too scary to venture out in such an insane time."

The American counteroffensive had begun in an area called the Yarmouk Circle and later spread to other neighborhoods in the south of the city, said Lt. Col. Paul Hastings, a spokesman for the task force that includes the Stryker Brigade. Insurgents melted away whenever the brigade's high-speed vehicles approached, he said.

Colonel Hastings said the insurgents had made only limited inroads. "There are pockets of insurgents," he said. "The city is not falling apart by any stretch of the imagination."

An Iraqi reporter for The New York Times who drove around Mosul on Thursday saw some Stryker vehicles in the suburbs and on the highway to the airport, but few in the city. He encountered no Iraqi policemen, but saw carloads of insurgents brandishing Kalashnikovs and rocket-propelled grenade launchers

The government center in the middle of town came under attack by guerrillas. A self-proclaimed holy warrior who gave his name as Abu Ibrahim said by telephone that his comrades had overrun the center by 6:30 p.m. But a government employee, Said Jasim Muhammad, said by telephone Thursday evening that American and Iraqi forces had defended the center.

"The building is still under American protection, and I'm in it right now," Mr. Muhammad said.

There were other failed attacks. The guerrillas tried to seize a television and radio broadcasting building but were repelled by security forces. They stormed a pediatric hospital, only to have the workers persuade them to leave.

Mosul is a diverse city with large numbers of Sunni Muslims, Christians and Kurds. It seems clear that the Sunnis are spearheading the attacks. It is less obvious who is leading them.

On Wednesday, as guerrillas fought American troops in eastern neighborhoods, the American military began dropping leaflets picturing Abu Musab al-Zarqawi, the Jordanian militant who is Iraq's most wanted insurgent leader.

Brig. Gen. Carter Ham, the commander of American forces in northern Iraq, said in an e-mail message that the leaflet drop was nothing new. The military just wanted to remind people that there was a $25 million reward for Mr. Zarqawi, he said.

In the early hours of Friday, mosque loudspeakers in a fundamentalist neighborhood called Al Ar Rabi blared a simple message: "Don't go outside tomorrow because it will be a big day."