A monkey has been blamed for triggering a nationwide blackout in Sri Lanka after the animal intruded into a power station.

The blackout occurred when the monkey found its way into the Panadura power station, south of Colombo, and came into contact with a grid transformer, according to Kumara Jayakody, the energy minister.

The disruption cut power across the island country, leaving millions without electricity for hours, and affecting hospitals, water purification plants, and railway systems.

“A monkey has hit a transmission line inside a power station, causing an immediate imbalance in the system and the national grid shut down,” Mr Jayakody told reporters.

A security guard at the Panadura power station said he heard a loud explosion followed by a ball of smoke rising from the power station.

The monkey died on the spot, he said.

Many have been forced to rely on generators since the blackout started at about 11.00am local time (5.30am GMT) on Sunday. Residents were asked to disconnect their solar power systems and use water sparingly until the power supply was restored.