Northumbria Police and members of South Shields Volunteer Life Brigade (SSVLB) were alerted to part of Sandhaven beach in South Shields at 8.35pm yesterday
A spokesman for the SSLVB team said: "The brigade was tasked to reports of a male in the water behind the Sand Dancer pub.
"On arrival the police were with the person who was just taking a dip and refused treatment by ambulance crews.
"The team were stood down and the police left the scene.
"A short time later the male entered the water once more and police responded.
"As they were concerned for his welfare the gentleman was taken into police custody."
The incident was brought to a close at 9pm.