Nakhon Ratchasima: A Thai soldier who killed at least 26 people before being shot dead in a mall by commandos went on the rampage because of a debt dispute, the kingdom's premier said on Sunday, offering the first official speculation for the motive of an "unprecedented" shooting spree.

After a night, which seesawed between heavy exchanges of gunfire and terrifying dashes for mall exits by trapped shoppers, sharp-shooters brought an end to the 17-hour-ordeal when they killed the gunman on Sunday morning in Nakhon Ratchasima, also known as Korat. Twenty-six people including civilians — the youngest a 13-year-old boy — and security forces were killed by the rogue soldier, Thailand's prime minister Prayut Chan-O-Cha said.