Iranian officials said today they were losing hope of pulling any survivors from the rubble of a collapsed Tehran high-rise where around 20 firefighters were feared to have lost their lives.<br/>'<br/>Rescue workers, soldiers and sniffer dogs were still searching through the wreckage of the 15-storey Plasco<br/>building in downtown Tehran, which collapsed yesterday after a four-hour blaze. But smouldering fires and smoke were complicating the search, and no survivors or bodies had been found.'<br/>'<br/>The ISNA news agency said a total of 111 people were injured, of whom five were still in hospital.'The Plasco building was Iran's oldest high-rise and<br/>contained a shopping centre and hundreds of clothing<br/>suppliers.'<br/>