One of a group of tombstoning teenagers was arrested on Brighton seafront yesterday (Monday 1 August).
Tombstoning involves jumping into the water from a considerable height.
Sussex Police said that lifeguards asked officers to speak to the group over fears for their safety.
One of the group, a teenage boy, was arrested for using abusive language under the Public Order Act.
He was released without further action after being spoken to about his behaviour.
He led the crew that rescued a man who was thought to be seriously injured after jumping 40ft from the Palace Pier in Brighton into just 3ft of water last month.
Fortunately the man’s injuries turned out to be relatively minor.
Mr Bell accepted that it was probably impossible to stop people from tombstoning but he gave a warning about the dangers and said: “It’s very difficult to judge the depth of water when looking down on it.
“There are often tides and currents which can take you away from safety and there are often hazards and rocks at or just beneath the surface.
“No one’s expecting it to stop.
“We offer advice to reduce the risks if anyone is taking part in tombstoning.
“Check the depth of water beneath you, have a look and make sure there are no hazards, no rocks that are just underneath the surface.
“Check the tides and the currents, don’t jump under the influence of alcohol or drugs and have a look around you and make sure there are no young people looking to imitate.”
The RNLI has been called out to 98 tombstoning incidents in the past five years and rescued 58 people. At least 14 people have died from tombstoning over the same period.
Mr Bell’s interview was preceded by one with Sonny Wells, 23, from Waterlooville in Hampshire.
The former soldier was paralysed three years ago when he jumped 30ft off the pier into 3ft of water in Southsea in Portsmouth.
He said: “It’s probably one of the worst things that you could be told to be honest that you’re not going to be able to walk again or just knowing that you’re paralysed.
“I kick myself every day for doing it.
“It’s not what it just does to you. It’s what it does to your family, your friends.
“I have to have people on standby or on call in case things go wrong.
“It’s not just my life that’s changed. Their lives changed as well.”
His mother, Jacqui Unal, 45, said: “He’s stuck in a wheelchair 24/7.
“If you want to end up like that then all I’d say is go ahead and jump.”
* The RNLI Brighton is holding its annual open day on Sunday 28 August from 11am to 4pm at the charity’s lifeboat station at Brighton Marina. The crew will also take part in the 999 Fun Day on Hove Lawns by the Peace Statue on Sunday 21 August from 10am to 4pm along with the police, fire and coastguard services.