An investigation has been launched after around 1,000 litres of liquid containing ferric chloride spilled at the Punta Brava wastewater treatment plant in Puerto de la Cruz, Tenerife, with possible deliberate interference among the circumstances being examined.

The incident occurred on Saturday night after a small rupture appeared in a hose which had undergone maintenance and repair work earlier that day.

According to information provided by the Tenerife Cabildo, the spilled mixture consisted of approximately 75% water and 25% ferric chloride, a chemical commonly used during water and wastewater treatment.

Aqualia, which operates and maintains the facility, reported that the hose had been left in good condition following the earlier repair.

However, security cameras at the plant reportedly recorded an unauthorised person entering the facility and heading towards the area where the rupture subsequently occurred.

Possible sabotage is therefore one of the lines being investigated, although authorities have stressed that no conclusion has yet been reached about what caused the damage.

The Tenerife Island Water Council has opened an investigation and requested detailed information from Aqualia about the incident, including the circumstances surrounding the spill, the amount released, the measures taken afterwards and whether appropriate safety and environmental protocols were followed.

There are also conflicting accounts over whether the liquid remained completely within the treatment plant.

Initial information indicated that the entire spill had been contained inside the facility. However, the Cabildo has since acknowledged differing versions of events and says investigators must establish whether any of the liquid entered the stormwater drainage system and potentially reached the sea.

Inspections and sampling are being used to determine what happened and assess the potential environmental impact.

Puerto de la Cruz Local Police have inspected the facility, while officers from the Guardia Civil's environmental protection unit, SEPRONA, have also attended as part of the investigation.

The Cabildo says it will not rule out any possibility until the investigations are complete and has warned that appropriate action will be taken if failures or responsibilities are identified.