RAF MILDENHALL, England — Officials are remaining mum on what caused 50,000 gallons of firefighting foam to be released at RAF Fairford in July, but the Fairford village mayor said this week that he was told the spill was caused by a faulty fire suppression system.

Air Force and British Environment Agency representatives said they could not comment due to ongoing investigations into the spill, which led to about 700 fish being killed in a nearby brook. The foam eventually made its way into the River Thames before dissolving on its own.

John Morgan, the mayor of Fairford, said officials told him shortly after the incident that the fire alarm system was to blame.

The fire suppression system and subsequent foam release was somehow activated when no one was in the hangar, Morgan said he was told.

And then the foam just flowed, he said.

“There was nobody to turn the thing off,” he said.

Morgan said he asked base officials to try to adjust their system to prevent a similar incident in the future, and that he was told the same thing also had happened at other bases.

After the foam’s release on July 5, the agency issued a warning to residents that the foam could cause eye and throat irritation.

Environment Agency spokesman Peter Ferguson said this week that there is no timetable for when the agency’s investigation will be completed, or what kind of action might be taken after that.

Water pollution and any fines or criminal penalties for such an incident would fall under the U.K.’s Water Resources Act.

Ferguson said shortly after the incident that it’s difficult to say if any charges will come as a result of the spill.

Sign Up for Daily Headlines

Sign-up to receive a daily email of today’s top military news stories from Stars and Stripes and top news outlets from around the world.

Sign up