Police and fire crews were spotted at The Lagoon in Welwyn Garden City last night, leaving many residents wondering what was happening.

The presence of the emergency services led to concern that a serious incident was taking place, but the Welwyn Hatfield Times can now confirm that a training exercise for a person in water was taking place.

"This was a training exercise for a person in water led by the fire and rescue service. We were invited to attend and sent two officers along," a Herts police spokesperson.

A spokesperson for Hertfordshire Fire and Rescue confirmed the same, saying: "There wasn’t an incident there last night. Local crews were carrying out a water rescue training exercise."