Four beaches in Benalmadena have been closed to swimmers after around 20 people suffered mysterious skin reactions on Sunday.
Benalmadena Town Hall initially ordered the closure of Las Gaviotas, also known as Santa Ana, after several bathers reported developing rashes and other reactions after entering the water.
The first alert was received by the 112 emergency service at around 12.30pm, prompting authorities to raise the red flag and begin checks for possible contamination.
But the precautionary measure was later extended to the beaches of Bil-Bil, Arroyo de la Miel and Los Melilleros.
Municipal sources said around 20 cases of skin eruptions had been detected among swimmers along the affected stretch of coastline.
The cause remains unknown and officials are carrying out tests to determine whether some form of contamination is present in the sea.
The town hall has urged beachgoers to respect the red flags and follow instructions from lifeguards and security personnel.
The incident comes during one of the busiest weekends of the summer on the Costa del Sol and just a day after swimming was discouraged at four beaches in Malaga city following storm-related discharges into the sea.
Campo de Golf-San Julian, La Misericordia and Sacaba returned to green-flag status on Sunday, while San Andres remained under a red flag as cleaning work continued.
There is currently no confirmed connection between those discharges and the skin reactions reported in Benalmadena.
Read more Andalucia news at the Spanish Eye.
