A major search operation is under way after reports a 14-year-old boy disappeared while swimming in the River Mersey.
The emergency services received calls shortly after 19:00 BST on Sunday to say the boy had been in the water with friends, near the radar tower on Crosby Beach.
Merseyside Police said the rest of the group had come out of the river but realised they had become separated from the teenager and had not seen him since.
The coastguard, police, fire and rescue units, helicopters and the ambulance service were all involved in the search overnight.
A section of Crosby Beach near the radar tower has been cordoned off as the search continues.
Merseyside Police urged people to avoid the area.