BEIJING, Oct 4 (Reuters) - Spectators may be invited to attend Beijing 2022 Olympic test events, organisers said on Monday, in a possible indication of what to expect at next year"s Winter Games. Beijing 2022 officials, however, declined to give further details on the plans for spectators, including COVID-19 requirements and how to buy tickets. "If conditions allow we will arrange for spectators to attend certain competitions," Yao Hui, Director of Beijing 2022"s Venue Management Department, told a news conference, referring to test events starting this week at the National Speed Skating Oval and at eight different Olympic venues before the end of the year. Foreigners taking part in the test events must have had a COVID-19 vaccine and on arrival in China must stick to rules such as limiting their movements to competition and training venues. The presence of over 2,000 international participants presents a "massive test" for organisers, said Huang Chun, Deputy Director of Beijing 2022"s COVID-19 Prevention and Control Office. "This will undoubtedly and clearly increase the risk of the import and spread of COVID-19," Huang said. Tickets for the Beijing Winter Olympics will be sold to spectators from mainland China only, while unvaccinated athletes must spend 21 days in quarantine ahead of the Games, the International Olympic Committee said last week. The Games start on Feb. 4 and the Chinese capital will become the first city to have hosted both summer and winter Olympics after also staging the 2008 summer Games.