A World Health Organization (WHO) driver has been killed in a conflict-riven region of Myanmar while out collecting Covid-19 monitoring samples.   Pyae Sone Win Maung was driving a well-marked United Nations vehicle when it was hit by gunfire in Rakhine State. The UN says dozens of civilians have been killed as fighting between the military and the armed ethnic Arakan Army group escalated in recent weeks. The two sides have blamed each other for the WHO driver's death on Monday. Both the military in Myanmar (also called Burma) and the Arakan Army deny being involved. Myanmar's Maj-Gen Tun Tun Nyi, a military spokesman, said his forces had no reason to attack the UN vehicle. "They are working for us, for our country," he told Reuters news agency. "We have the responsibility for that. The UN office in Myanmar said it was "deeply saddened" by the 28-year-old driver's death, near a military checkpoint in Minbya township. According to a post on Facebook, the marked vehicle was travelling from Sittwe to Yangon bringing Covid-19 surveillance samples "in support of the Ministry of Health and Sports". The UN did not say who carried out the shooting, which also left a government employee injured. The driver's father, Htay Win Maung, said his heart was "broken". "I am trying to calm myself thinking he died in serving his duty at the frontline," he added. "He went there in the midst of fighting when many people didn't dare to go." Countries including the UK and the US have called for an end to fighting amid the global coronavirus pandemic. More than 80 cases have been reported in Myanmar, along with four deaths. The Arakan Army, ethnic Buddhists who have escalated their campaign for self-rule in the last two years, declared a month-long ceasefire, but this was rejected by the government.