SINGAPORE - Three girls from Changkat Changi Secondary School were taken to KK Women's and Children's Hospital on Friday morning.
Their schoolmates had told The Straits Times that the pupils left during the school's half-hour Total Defence Day parade.
But its principal said that the complaints occurred at different times and at separate parts of the school, adding that the cases were unrelated.
Only one girl had become dizzy after participating in the parade. One of the other girls had complained of giddy spells before school started and was taken to the sick bay, while the third fell ill in the classroom.
The Singapore Civil Defence Force said three calls were made before 9am requesting for ambulance assistance at the school in Simei.
Two of the girls have been discharged while another is currently hospitalised for further observation, said the principal.