Hong Kong's travel warning for most of Japan remains at the second-highest level, though Japan has raised the alert level at the stricken nuclear plant from four to five on a seven-point international scale for atomic incidents.
Japan's lifted alert gave fresh weight to demands by many lawmakers to change the city's warning status from red, meaning 'adjust travel plans' and 'avoid non-essential travel', to black, the top level, meaning 'avoid all travel'. They said the government should work better to guarantee people's safety.
Hong Kong has a black alert only for Miyagi, Fukushima, Ibaraki and Iwate prefectures.
Undersecretary for security Lai Tung-kwok defended the warning again yesterday.
Lai said Japan's change of alert level 'only indicated what had happened', and that it did not change the fact that the degree of radioactivity in places other than the four prefectures remained normal.
The Hong Kong government is urging its residents to leave Tokyo because of the worsening situation at the Fukushima nuclear power plant.
Dr Law Chun-key, president of the Hong Kong College of Radiologists, said travellers 'better leave earlier than not'. He said: 'There is no immediate risk [of contamination by radiation]. But the longer one stays, the riskier it is.'
Demand for seats on flights from Tokyo to Hong Kong had been high, Cathay Pacific said, but that there were sufficient flights to cater to all wanting to travel.
Two extra flights brought at least 150 people from Tokyo to Hong Kong last night. There will be one flight a day until Monday.
'At the moment we are doing well; everyone who wants a seat can get one,' said Tony Tyler, the carrier's chief executive, adding that there were still empty seats on every extra flight from Tokyo to Hong Kong.
'We are seeing a lot of no-show passengers - people not turning up - and we are seeing a lot of go-show passengers - people turning up without reservations or even tickets.'
Cathay said flights from Hong Kong to Japan were not full and most passengers were returning Japanese. Tyler said all flight meals, including those on returning flights, were sourced in Hong Kong.
Meanwhile, a team of 25 government officers, mainly from the disciplinary force, has been sent to Tokyo to help Hongkongers arrange to return. The team arrived yesterday.
'It is a support team, not a rescue team,' Lai said. 'Their main responsibility will be to help Hongkongers there.'
Chief Executive Donald Tsang Yam-kuen called on Hong Kong people last night not to panic, because the city had not been affected by the nuclear incident in Japan.
Law said people did not need to worry about contamination from exposed people, as the risk was minimal. 'The risks of suffering from an overdose are small,' he said.
Symptoms of radiation overdose are similar to that of a cold, according to Dr Choi Yu-fai, from the Hong Kong College of Emergency Medicine.
'Patients may suffer from nausea, fever and diarrhoea within 48 hours of exposure to radiation,' he said. The doctor recommended that travellers with such symptoms undergo the voluntary radiation scan at Hong Kong's airport.
Dr Yu Kai-man, spokesman for the Hong Kong College of Obstetricians and Gynaecologists, advised pregnant women to pay extra attention, because fetal development is particularly prone to radiation.
When pregnant mothers are exposed to more than 150 millisieverts of radiation - that is, 50 times the normal level in the environment - their baby's growth could be restricted, he said. When their exposure to radiation exceeds 500 millisieverts, serious deficiencies may result and the chance of miscarriage increases.