A fuel leak has spread for more than two miles along the River Taff, Public Health Wales said, prompting health guidance for nearby residents to limit exposure to odours.
Public Health Wales advised people living in the affected area to close doors and windows because of the smell. The notice was issued as the spill was reported to have extended along a stretch of the river exceeding two miles in length.
Fuel spills in waterways can present multiple hazards, including risks to air quality from volatile vapours and potential harm to aquatic life and water supplies. Authorities commonly recommend limiting outdoor exposure and sealing homes as an immediate precaution while the situation is assessed.
Public Health Wales is the body that issued the advice; further operational details about containment, cleanup or the cause of the leak have not been released in the initial notice. Residents are being urged to follow official guidance and await further information from public health and environmental agencies.