Hundreds of children at one of Wales' biggest schools have been sent home to self-isolate after a pupil tested positive for coronavirus.
Olchfa Comprehensive School has sent letters to parents of those affected advising them of what they have to do.
A total of 455 sixth formers must stay at home for two weeks. No staff are self-isolating.
Head teacher Hugh Davies has told parents of other pupils at the Swansea school that they may still attend.
Swansea Council said the rest of the school was running normally and the authority was working with Public Health Wales and NHS Wales' Test Trace and Protect service to ensure appropriate measures were in place to protect students, staff and the wider community.
A spokesman said: "All close contacts of the case have been identified and have received appropriate advice to self-isolate. Children who have not been identified as a close contact do not need to self-isolate and do not require testing for the virus."
The letter to parents of children who were not close contacts of the child with the positive test also advised them to continue to keep an eye on their children as a precaution.
It said parents should be alert to any symptoms of Covid-19 and should self isolate if they develop symptoms.
It is believed that more than 50 schools across Wales have reported Covid-19 incidents to date.
All Year Seven children at two Newport secondary schools were told to self-isolate after pupils tested positive for coronavirus.
At Bridgend's Bryntirion Comprehensive School, more than 200 pupils were sent home.
In Cardiff, eight children and three staff at Llanishen Fach Primary School were asked to self-isolate, while 57 youngsters and two employees at Whitchurch High School were also sent home.