Afghan forces battled the Taliban in a key provincial capital for the fourth straight day on Monday, following a massive assault on Ghazni last week that overwhelmed its defenses and allowed insurgents to capture several parts of it, officials said. The assault on the capital of Ghazni province was a major show of force by the Taliban, who infiltrated deep into the strategic eastern city barely 120 kilometres from the capital, Kabul. The United States has sent military advisers to aid Afghan forces, and President Ashraf Ghanis office announced Monday reinforcements for Ghazni. The multi-pronged attack on the city began on Friday, with insurgents infiltrating peoples homes and slipping out into the night to attack Afghan forces. The fighting since has been ferocious and many Afghan troops and insurgents are believed to have died in the battle so far. Few details have emerged from Ghazni since the Taliban destroyed a telecommunications tower on the citys outskirts, cutting off all landline and cell phone links to the city and making it difficult to confirm details of the fighting. But Ghazni residents told AFP late Sunday that the dead bodies of militant and soldiers continue to litter the streets, while government offices have been set ablaze by Taliban fighters. The citys power remained cut, with food prices rising, they said. The fall of Ghazni, a city of 270,000 people, would mark a major victory for the Taliban. It would also cut off a major highway linking Kabul to the southern provinces, the Talibans traditional heartland. Meanwhile, a suicide attacker detonated explosives near the office of Afghanistans election commission in Kabul on Monday, where dozens of protesters had gathered, officials said. At least one police official was killed and one officer was wounded. The protesters had gathered in support of a parliamentary candidate who electoral officials had disqualified over his suspected links with "illegal armed groups".