He told reporters that his back was still cold from the water sprayed on him, while photos showed the PM may have been doused by more than his fair share of chilly water.
Today’s water fight was the first one Prayut had attended since he was 15, he told reporters. After joining the military, he had little time for water guns.
Prayut made merit at three temples in Bangkok before heading to Khao San Road.
He was joined by other members of the United Thai Nation Party, including party leader Pirapan Salirathavibhaga. Prayut is the party’s candidate for prime minister in the May 14 election.
They made merit at Wat Phichai Yat, Wat Hong Rattanaram and Wat Rakang, the temple he frequently visited when he was Army chief.
Prayut said he visited the temples to make a wish for the country. Thailand is at peace as many tourists are visiting, he said.
While visiting the temples, he asked people to vote for the UTNP in the May 14 election. He wished success for all and said he hoped they enjoyed themselves during the festival.
After making merit, Prayut showed up on Khao San Road with a water gun.
Tourists and police officers were startled by his unannounced arrival. Many asked: "Is he the real Prayut?"