Baghdad, Iraq ? Iraqi insurgents, run out of their northern stronghold in Tal Afar for the second time in a year, counterattacked with an Internet propaganda offensive Monday that put a bounty of about $200,000 on the heads of top Iraqi leaders.

Violence flared again in the ancient city late Monday when Iraqi soldiers trapped insurgents in basement hideouts, killing 40 militants in fierce combat, the military said. Most insurgents had fled Tal Afar as the U.S.-backed offensive began Saturday, many escaping through tunnels.

The new fighting raised the insurgent death toll in Tal Afar to nearly 200, the government said. Officials said seven Iraqi soldiers and six civilians died in the three-day offensive, while the U.S. military said no American soldiers were hurt.

Prime Minister Ibrahim al-Jaafari flew to Tal Afar on Monday to congratulate his army, and Al-Iraqiya state television said he went despite insurgent threats “to attack the city with chemical and biological weapons.”

There was no known public threat from the insurgents to use unconventional weapons in Tel Afar, but militants made two Internet postings in recent days vowing to stage chemical attacks on Baghdad’s Green Zone – home to the U.S. Embassy, Iraq’s parliament and government offices.

Iraqi soldiers advance in an operation Monday in Tal Afar, northwestern Iraq. Iraqi Prime Minister Ibrahim al-Jaafari said troops are in high

The Islamic Army in Iraq, which has previously claimed responsibility for kidnappings and killings of foreigners, made the bounty offer for the assassination of key Iraqi officials.

The militant group called in a Web posting for its “holy fighters to strike the infidels with an iron fist.” It offered $100,000 to the killer of al-Jaafari, $50,000 for the interior minister and $30,000 for the defense minister.

Iraq’s U.S.-trained forces and U.S.-backed government are waging their own media offensive, using the Tal Afar operation to position themselves as a confident and strong team now leading the fight to wipe out insurgent forces.

“I met today with the commander of the 3rd Division in Tal Afar and his officers and soldiers and found them in high spirits,” al-Jaafari said. Hundreds of Iraqis danced, sang and waved flags as the prime minister toured the region.

The U.S. 3rd Armored Cavalry Regiment, which sent 3,500 soldiers in support of the 5,000-member Iraqi force, appeared to minimize its role in Tal Afar in favor of a high profile for the increasingly muscular Iraqi military.

Interior Minister Bayan Jabr said the insurgents were turning to Internet threats because the Tal Afar offensive had badly shaken the militants.

“It was a great shock to al-Qaida. They were thrown off balance and issued this threat,” he said at a news conference.

The insurgents’ threat to use chemical weapons was not being taken lightly. Last month, U.S. troops raided an insurgent hideout in the north that the U.S. military said may have produced chemicals for use against coalition forces. About 1,500 gallons of various chemicals were found in the hideout in Mosul, which is 35 miles east of Tal Afar.

“There were 11 precursor chemicals, which are dangerous by themselves, and mixed together they would become even more dangerous,” Lt. Col. Steve Boylan, a military spokesman, said at the time.