The mystery closure of a Kilmarnock pool was due to a 'diarrhoea incident'.
A boss at the Galleon Centre confirmed that the outbreak took place yesterday evening.
Since the incident a super deep clean of the pool has been underway and the pool has remained closed since.
But bosses are now hopeful of reopening the pool this afternoon.
David Hasson, Galleon acting general manager said: "Unfortunately we had to close the pool around 5.30pm yesterday as one of our bathers had diarrhoea during swimming lessons.
"Diarrhoea is likely to contain bacteria and viruses and may also contain cryptosporidium.
"Under health and safety guidelines we have strict procedures to follow to ensure the safety of all swimmers.
"This means closing the pool for a period of time to allow us to go through the process of chlorination and backwashing.
"We hope to be open this afternoon but we will keep everyone up to date on our Facebook page."
A statement on the Galleon's Facebook page read: "Unfortunately we had to close our pool yesterday evening due to an incident of diarrhoea.
"Our standard operating procedure is to close the pool immediately for super-chlorination and carry out a deep clean of the pool, surround, showers and changing facilities, in accordance with PWTAG guidelines.
"This procedure can take up to 15 hours before we lower chlorine levels back down to operational levels.
"We are in the process of bringing levels down and will post an update on likely opening times by 12pm today."
