One of the two men arrested over last month's deadly Bangkok bombing has admitted to a charge of possessing explosives, Thai police said Monday, in the first confession over the attack.

"We have informed him of the charge. He acknowledged and confessed to the charge," national police spokesman Prawut Thavornsiri told reporters.

Thai police on Friday said neither of the two men detained over the deadly Bangkok attack last month were believed to be the main bombing suspect -- seen on CCTV wearing a yellow t-shirt and placing a rucksack under a bench at Erawan shrine moments before the blast.

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