Three operators of fish farms that are set up in the southern area of Malta have been ordered by the environmental watchdog to clean up slime that reached the coast over the weekend.

The Environment and Resources Authority is meanwhile looking into reports of slime off Pembroke and St Julian's.

It said in a statement on Monday that after confirming sightings of slime in the southern area of the island, it had asked three farm operators to clean up St Peter’s pool, il-Bajja ta’ San Tumas and Marsascala swimming zones.

ERA coordinated the clean-up together with Transport Malta and the Police.

A Marsascala bather told Times of Malta that on Sunday the water and rocks were "covered in an oily white and sticky slime".

"This is the worst I've experienced it because it stuck to my skin, and equipment and wouldn't wash off. Yuck. It felt like I was slimed in Ghostbusters," they said.

"I thought this fish slime from the fish farms was supposed to be a thing of the past after all the regulations, but it's clearly back. It's not a 'natural' phenomenon. There were children, the elderly, and families swimming in that water. The seas are being treated like a dump."