MOSUL/SULAIMANIYA, Iraq Iraqi forces saw off an overnight Islamic State counter-attack near Mosul's main government buildings and took full control on Wednesday of the last major road leading west to the militant-held town of Tal Afar, the military said. Troops also captured the Badush prison, northwest of Mosul near the road, where Islamic State reportedly executed hundreds of inmates in 2014, another military statement reported by state TV said. Inside Mosul, troops battled the ultra-hardline Sunni Muslim fighters, who hid among the remaining civilian population and deployed snipers and suicide car bombs to defend their last major Iraq stronghold. The U.S.-backed campaign to crush the militants saw Iraqi forces recapture the eastern side of the city in January. They launched their assault on the western half last month. Islamic State leader Abu Bakr al-Baghdadi declared the group's self-styled caliphate, which has spanned areas of northern Iraq and eastern Syria, from the Nuri Mosque in Mosul's old city in June 2014. Fighting is expected to get tougher as Iraqi troops push further into the more densely populated areas in the western half of the city, including Mosul's old city. Militants used car bombs in their nighttime counter-attack around the Nineveh governorate building, Major General Ali Kadhem al-Lami of the Federal Police's Fifth Division told a Reuters correspondent near the site. "Today we're clearing the area which was liberated," he said. Military officials had said that Rapid Response troops, an elite interior ministry division, recaptured the provincial government headquarters on Tuesday. They also took the central bank branch and a museum where militants had filmed themselves destroying priceless statues in 2015. "The museum is completely empty of all artifacts. They were stolen, possibly smuggled," Lami said. Reuters could not get access to the museum to verify his comments. Lami said most of the fighters that had fought around the governorate building were local, but some were foreigners. "An order was issued for foreign fighters with families to withdraw with them. Those who do not have a family should stay and fight, whether foreign or local," he said. The few families remaining in the nearby Dawasa district said the militants had set some of their homes on fire as security forces advanced and that the militants had fought among themselves. LAST ROAD FROM MOSUL Later on Wednesday, the Iraqi military said the army and Shi'ite paramilitary forces had taken full control of the last major road leading west out of Mosul towards the town of Tal Afar, state TV reported. The 9th Armored Division and two Shi'ite fighting groups had "isolated the right bank (western side of Mosul) from Tal Afar", it said. The road links Mosul to Tal Afar, another Islamic State stronghold 60 km (40 miles) to the west, and then to the Syrian border. Shi'ite militias taking part in the Mosul campaign began to close in on Tal Afar late last year, after the offensive was launched. They linked up then with Kurdish fighters to encircle the jihadists. A 100,000-strong force of Iraqi military units, Shi'ite forces and Kurdish fighters, backed by a U.S.-led coalition, have fought since October in the Mosul campaign. Losing Mosul would deal a fatal blow to Islamic State's hold over territory in Iraqi. At their peak, the held large areas of Iraq and neighboring Syria. The ultra-hardline jihadist group has lost most of the cities it captured in northern and western Iraq in 2014 and 2015. In Syria, it still holds Raqqa city as its stronghold, as well as most of Deir al-Zor province. But it losing ground to an array of separate enemies, including U.S.-backed forces and the Russian-backed Syrian army. It has carried out bombings in Iraqi and Syrian cities as its caliphate has shrunk. Iraqi Prime Minister Haider al-Abadi said Iraq would continue hitting Islamic State targets in Syria and in neighboring countries if they give their approval. Abadi on Feb. 24 announced the first Iraqi air strike on Syrian territory, targeting Islamic State positions in retaliation for bomb attacks in Baghdad. "I respect the sovereignty of states, and I have secured the approval of Syria to strike positions (on its territory)," Abadi told a conference in the Iraqi Kurdish city of Sulaimaniya on Wednesday. "I will not hesitate to strike the positions of the terrorists in the neighboring countries," he said. We will keep on fighting them."