BANGKOK, July 18 (Reuters) - Police used tear gas, water cannon and rubber bullets to disperse protesters trying to march on Thai Prime Minister Prayuth Chan-ocha"s office on Sunday to demand he resign over his handling of the coronavirus pandemic and its economic impact. Some protesters attacked police and eight police officers and at least one reporter were injured during the clashes, police said. Police did not say if any protesters were injured, but said 13 protesters were arrested. Protest organizers called for the demonstration to end just after 6 p.m. but a stand-off between the police and hundreds of protesters continued for several more hours before the police dispersed the crowd just before the start of a 9 p.m. curfew that is in force in the Thai capital. More than 1,000 people had joined the demonstration. Police intervened with force after some protesters tried to dismantle barbed wire and metal barricades set up by the authorities to block roads from Democracy Monument to Government House where the prime minister works. Deputy police spokesman Kissana Phathanacharoen said the protesters attacked police with "ping-pong bombs, sling shots and fire crackers". He added that the police actions followed laws and regulations and fully complied with international standards in controlling crowds. Anti-government protesters hold a placard with a picture of Thai Prime Minister Prayuth Chan-ocha, as they march toward the Government House, demanding Prayuth Chan-ocha resignation, mandatory vaccination policy and reform in the monarchy, in Bangkok, Thailand, July 18, 2021. REUTERS/Chalinee Thirasupa Mock body bags lay on a picture of Thai Prime Minister Prayut Chan-o-cha to depict casualties of the coronavirus disease (COVID-19) outbreak, during an anti-government march from Democracy Monument to Government House, in Bangkok, Thailand July 18, 2021. REUTERS/Soe Zeya Tun Protesters show the three-finger salute during an anti-government march from Democracy Monument to Government House, in Bangkok, Thailand July 18, 2021. REUTERS/Soe Zeya Tun 1/5 Mock body bags lay on a picture of Thai Prime Minister Prayut Chan-o-cha to depict casualties of the coronavirus disease (COVID-19) outbreak, during an anti-government march from Democracy Monument to Government House, in Bangkok, Thailand July 18, 2021. REUTERS/Soe Zeya Tun Street protests against the prime minister have been held in recent weeks by several groups, including Prayuth"s former political allies, as frustrations grow over the mounting coronavirus infections and the damage the pandemic has done to the economy. read more Thailand reported 11,397 infections and 101 deaths on Sunday, bringing the cumulative total to 403,386 cases and 3,341 fatalities, the vast majority from an outbreak since early April that is being fueled by the highly transmissible Alpha and Delta COVID-19 variants. read more Many protesters on Sunday carried mock body-bags to represent coronavirus deaths. "The government has been poor at managing the situation and if we don"t do anything there will be no change," one protester, Kanyaporn Veeratat, 34, told Reuters. The protest marked one year since the first of a wave of large-scale street protests led by youth groups that attracted hundreds of thousands of people across the country. The momentum of those protests stalled after authorities began cracking down on rallies and detaining protest leaders, and after new waves of COVID-19 infections broke out. ($1 = 32.7900 baht)