KUANTAN - Seaside residents and visitors here were shocked by the transformation of Pantai Batu Hitam into a red sea, following a heavy downpour the night before.
Trader Anita Awang, 38, said the sea had been a murky shade of red since morning, prompting many of her customers to take photos of the unusual sight.
"My husband figured it was just sand stirred up, but when I ran my hand through the water it was really red, not gritty grey like when it's sand," she said.
The Kuantan-native said it was the first time she had seen such a phenomena, adding that the colour was even more evident during high tide, around 8am.
Keropok seller Esah Awang (no relation), 68, said Pantai Batu Hitam often become muddy during the monsoon season.
"Yeah, but this year is even worse," said the trader, who had moved to Beserah over 50 years ago.
She warned that it was dangerous to swim at the beach when the water turned colour, for fear of any number of contaminants.
A check by The Star along the Beserah-Kuantan road that ran parallel to the sea painted a similar picture of pollution along the stretch.
By around 3pm, the tide had receded leaving the water a muddy brown instead.
Stop Bauxite Mining Movement (Geram) chairman Ali Akbar Othman said many residents had been posting photos of the red sea to the group's Facebook group page, prompting them to investigate the incident.
"This is exactly what we've been warning would happen," said Ali, referring to the danger of bauxite being washed into rivers and drains during the rainy season.
Bauxite mining had spread to the Beserah area, and was exacerbated by the large number of transport lorries carrying the red soil to Kuantan Port, in Gebeng, less than 15km away from Pantai Batu Hitam.