Twenty primary schoolchildren were taken to hospital after complaining of feeling unwell because of a pungent odour at their Tsuen Wan school yesterday.
Principal Tam Ying-to, of Tsuen Wan Government Primary School, said the odour was evident at about 8am when pupils arrived at the Castle Peak Road school.
'We could smell the odour in every corner of the school. It was so bad and very strong. We were unable to trace the source and had to call police,' she said.
Ms Tam said the smell was quite strong when fire engines and ambulances arrived at the school at about 8.30am.
Ten boys and 10 girls, aged between six and nine, complained of breathing difficulties or feeling nauseous and were taken to Yan Chai Hospital for treatment.
The school's morning assembly was cancelled and pupils were told to remain inside their classrooms while fire officers used a gas detector to trace the source of the smell.
