Police have arrested a woman after two children, aged seven and nine, were left trapped in a burning flat in Tsz Wan Shan.

Emergency personnel were called to Lok Moon House on Tsz Lok Estate after receiving multiple reports of the blaze before noon on Saturday.

Online footage showed flames and smokes billowing from the window of the home, which was close to the top of the block.

Rescuers were able to locate the children, a boy and a girl, both of whom were unharmed.

Their grandmother, 52, was arrested on suspicion of "ill-treatment or neglect by those in charge of child or young person" for leaving the pair unattended.

About 100 residents were evacuated from the building, although there were no reports of injuries.

A short circuit in a lamp was believed to be responsible for the blaze, according to preliminary investigations.