HONG KONG (Reuters) - Dozens of people in Hong Kong braved heavy rain on Friday evening to write postcards to 12 fugitives arrested by China at sea last month to offer comfort during the upcoming mid-Autumn festival. The 12 were arrested on Aug. 23 for illegal entry into mainland Chinese waters after setting off from Hong Kong in a boat bound for self-ruled Taiwan. All were suspected of committing crimes in Hong Kong related to the anti-government protests that erupted last year. Ten had been charged, released on bail and not allowed to leave Hong Kong, and all are now being detained in neighbouring Shenzhen. On Friday, activists set up booths in two districts to collect postcards, with several dozen passing through to leave their messages. “The security agency will see this postcard, but I don’t care,” wrote recent university graduate Zol Chan, 22, on her card. “Please take care of yourselves.” “Seeing their mothers crying in their press conference, I feel heartbroken and sad,” she said later. Relatives of some of the detainees held a news conference on Saturday to demand their urgent return and plead for them to be allowed to call home and consult lawyers appointed by the families and not the Chinese government. As he wrote his message, university student Raymond Cho, 19, said he felt a responsibility to tell them “that there are still a lot of us who care about them”. Ten of the detainees had been charged with offences such as manufacturing explosives, arson, rioting or assaulting police. One other was suspected of colluding with foreign forces under a national security law that Beijing imposed on Hong Kong in June. It is unclear whether authorities will allow the postcards to reach the detainees. This year, the mid-Autumn festival, a full moon harvest celebration across Asia, falls on Oct. 1, China’s national day. Police in Shenzhen said on Sunday they were suspected of illegal entry, their first public comment on the matter. The same day, China’s foreign ministry labelled the group as “separatists”. On Tuesday, Hong Kong leader Carrie Lam voiced discontent with the group being characterised by some as “democratic activists being oppressed”, saying they were running away from law. Lam said they would have to be “dealt with” by mainland authorities, but pledged to provide “feasible” assistance.