The reservoirs are not currently used for drinking water

Water company United Utilities says it received reports of discoloration at the reservoirs in Burnley.

Initial tests suggest this was caused by pollen but further investigations are being carried out.

Lancashire Police were carrying out searches around the water on Friday.

United Utilities says the reservoirs can be used to supply drinking water but are not being used for that purpose at present.

It is reassuring customers that their water is safe to drink.

Area search

Inspector Steve Samlesbury, from Lancashire Police, confirmed that an investigation was under way.

He added: "Officers are searching the area to gather evidence.

"At this stage there's no evidence of criminal activity and there are a number of possible reasons for the contamination.

"We are continuing to liaise with other agencies."