PHUKET, June 28 -- Thai authorities have ramped up security in Phuket, Songkhla and Chiang Mai this week following the discovery of multiple improvised explosive devices (IEDs) in popular tourist destinations along its Andaman coast.

The Bangkok Post reported that heightened alert comes after 29-year-old suspect Muhama Wadeng admitted to planting two IEDs near a construction site on Surin Beach, prompting an extensive search by explosive ordnance teams and police.

One device was located and destroyed, while efforts to find the second are ongoing. Officials said they are continuing their search to ensure the area is safe.

Other explosives were found at Promthep Cape and Patong Beach, while another device hidden in a motorcycle was destr...