Swimming at Balluta Bay is still not safe, health authorities warned on Saturday as they extended a contamination warning for an undetermined amount of time.

Authorities first issued a warning for the St Julian’s Bay on May 21 after discovering elevated levels of E.Coli bacteria in the water there.

E.Coli contamination is most commonly attributable to untreated sewage.

Water Services Corporation later denied responsibility for the contamination and said water in the bay and at the similarly contaminated St George’s Bay – was due to “third-parties” dumping waste at sea illegally.

The entire bay is not safe for swimmers, the directorate said.

On Saturday, the Environmental Health Directorate within the Superintendence of Public Health said Balluta Bay was still dangerous for bathers.

“Bathing is not recommended due to sewage overflow affecting the bathing water quality and presenting a risk to bathers’ health,” it said.

Work to determine the source of contamination is still underway.

The directorate said it could not predict how long the contamination would last.