The Taliban has captured an Afghan provincial capital after pleas for reinforcements by local security forces went unheard, in a major blow to the western-backed government. Zaranj, in the south-western province of Nimroz, fell after just three hours of fighting becoming the first provincial capital to be taken by the insurgents who have intensified their nationwide offensive as foreign forces withdraw from Afghanistan after 20 years of war. Late on Friday, heavily armed Taliban fighters driving captured Humvees were patrolling the streets of Nimroz, one of the country’s main financial hubs, where Taliban commanders declared an overnight curfew. “Nowhere in the entire Nimroz province is under government control – the Taliban has captured it all,” said one local official. “Security forces have either fled to other provinces or surrendered to the Taliban.” Officials in the city near the border with Iran said that government forces had called for reinforcements for more than a week, but their appeals went unanswered. About 3,000 people fled into Iran before the neighbouring country shut its border, according to residents. Locals with any connection to the government were in hiding, fearful of revenge attacks by the Taliban. “Taliban fighters are freely walking on the streets,” Shakib, a local resident, said by phone. “Anyone who could, fled to Iran last night before they closed the border. My family and I tried to escape too but we got there too late. Everybody is scared of our new rulers.” Taliban forces have swept across Afghanistan since launching their campaign in May, seizing swathes of rural territory. The insurgents did not initially target major urban areas, but are now threatening several large cities, such as Herat. Officials in Zaranj said government forces had been pleading for reinforcements for about 10 days, with no response. The attack on the city intensified on Wednesday this week after the Taliban over-ran a nearby district. Fighting on Friday was focused around the governor’s office, and the local police and intelligence headquarters and and ended when government forces retreated, a local official said. Taliban fighters also attacked the city’s prison and freed the inmates. “We don’t know where the local governor and police commander are – we only know they have fled Zaranj city over the afternoon,” another official said. Meanwhile, in Sheberghan, the provincial capital of Jawzjan, intense street-to-street fighting was under way on Friday and in Herat, government forces along with armed men loyal to the warlord Ismail Khan were exchanging fire in at least one part of the city. In Kabul, Taliban gunmen killed Dawa Khan Menapal, head of the government’s media and information centre, in the latest in a series of assassinations aimed at weakening President Ashraf Ghani’s democratically elected government. A Taliban commander, told Reuters that the capture of Zaranj marked a major strategic victory, considering its proximity to the Iranian border. “This is the beginning and see how other provinces fall in our hands very soon,” he said.