Puddles of animal blood were still present in Albertown yesterday next to the Marsa slaughterhouse, as the Water Services Corporation began its investigation and continued to clean up the area.

The deathly smell was replaced by a scent of disinfectant while the pieces of meat that had littered the road on Wednesday were removed.

Meanwhile, the department for environmental health said that, besides being a nuisance, such incidents "can also be of public health concern".

Residents living in areas where sewage overflows should avoid direct contact with any faecal matter, the department said.

According to mayor Francis Debono, who alerted the media to the matter, the blood outage was caused by abattoir workers because they probably let pieces of animal waste into the drainage system.

"Inside the abattoir there are meant to be grids filtering the waste but I suspect they are being removed to get rid of everything quicker," he said.

Meanwhile, the Ministry for Resources and Rural Affairs, together with the WSC, said the blockage in the drains was probably caused by illegal dumping.

The health department yesterday said it had not received any complaints about the issue but when alerted by this newspaper, health officers went to investigate.

"Till now the nuisance has not yet been entirely abated. Further investigations will be carried out this morning and officials from this department will be present to supervise this operation and to offer any possible assistance in order to try to trace the source of this blockage," a spokesman for the health authority said.

When contacted, a spokesman for the WSC said there were no updates yesterday, as the cause had not yet been identified.