A couple of teenage boys were rescued from a riverbank in Lancaster on Monday.
Police were called to new Quay Road just after 7.15pm but upon arriving there were no sign of any persons in the water.
A member of the public rang the emergency services after seeing the boys swimming along the riverbank.
Morecambe Coastguard were alerted.
It is believed the boys did not suffer any injuries.
Fire crews were also called just after 6.30pm but were not needed upon arrival.