Two separate cases of electrical short circuits on Monday morning were believed to have prompted hundreds of people to evacuate from their homes in Tsz Wan Shan and Tuen Mun respectively, with three people hospitalised for inhaling smoke.

The trio, aged 26 to 65, were sent to Queen Elizabeth Hospital to be treated for smoke inhalation, after a fire broke out at their flat's kitchen in Tsz Wan Shan.

Authorities said the incident at the Tsz Oi Court home happened at around 5am, forcing some 200 residents to evacuate.

The fire was put out within 20 minutes.

Initial investigations found the fire had been caused by an electrical short circuit in a kettle.

Around an hour later, about 100 other people were evacuated from Tuen Mun's Elegance Gardens as thick smoke billowed out from a flat.

It's believed that a short circuit in a thermo pot was to blame.