BAGHDAD: Iraq said on Monday it had put its Tikrit offensive on hold and senior officials called for more airstrikes to dislodge Islamic State militants who have laid explosives across the city and still hold its central districts.

The offensive, the largest yet against insurgents who swept through northern Iraq in June, has been stalled for four days after Iraqi security forces and mainly Shiite militia pushed into Tikrit last week.

They have struggled to gain further ground against the militants who are holed up in a vast complex of palaces built when Saddam was in power. Military officials in Tikrit said there was no fighting on Monday in the city that was home to more than 250,000 people before it was overrun last year.

Government forces are in control of most of the northern Qadisiya district as well as the southern and western outskirts of the city, trapping the militants in an area bounded by the river that runs through Tikrit. Though Iraqi forces and allied militiamen may have the insurgents in a chokehold, officials are increasingly citing air power as necessary to drive out the remaining insurgents. “We need air support from any force that can work with us against IS,” Deputy Minister of Defense Ibrahim Al-Lami told Reuters, refusing to say whether he meant from the US-led coalition or Iran.

Interior Minister Mohammed Al-Ghaban said authorities had put a temporary halt to the offensive in Tikrit. “We have decided to halt military operations in Salahuddin in order to reduce casualties among our heroic forces... and to preserve the remaining infrastructure,” the minister said.

Meanwhile, the tomb of Iraq’s late dictator Saddam Hussein was virtually leveled in heavy clashes. Associated Press video from the village of Ouja, just south of Tikrit, shows all that remains of Hussein’s once-lavish tomb are the support columns that held up the roof.

Poster-sized pictures of Saddam, which once covered the mausoleum, are now nowhere to be seen amid the mountains of concrete rubble. Instead, Shiite militia flags and photos of militia leaders mark the predominantly Sunni village, including that of Maj. Gen. Qassem Soleimani, the powerful Iranian general advising Iraqi Shiite militias on the battlefield.