South Korean authorities have deployed heat-seeking cameras and drones in a widening search for a runaway wolf that has been on the loose for three days after escaping from a zoo.

The two-year-old male, named Neukgu, burrowed under a fence at Daejeon O-World zoo and theme park in the central city of Daejeon on Wednesday, officials said.

More than 300 personnel - including firefighters, police officers and military troops - have been mobilised in the hunt for the animal, Daejeon Fire Headquarters said.

Addressing the incident on Thursday, President Lee Jae Myung said in a post on X: "I hope no human casualties occur and I pray that Neukgu also returns home safely."

A nearby elementary school was closed as a precaution on Thursday after the wolf remained at large, and authorities have urged residents to take care and report any sightings.