It is illegal to swim up to and jump off the Mulberry Harbour in Southend ... and coastguard teams are urging visitors to stay away.

The harbour has become a hotspot for swimmers getting cut off by the tide in recent months but it is illegal to get anywhere near it as the land nearby is actually owned by the Ministry of Defence.

The land is often used for bomb disposals.

The harbour has seen a rise in visitors ignoring advice and resulting in groups becoming stuck, prompting Southend’s Coastguard teams to re-iterate its messages.

It comes after groups, sometimes of up to 15 people, have been seen jumping off the harbour before getting cut off by the tide.

The most recent incident, on Monday night, required the coastguard to attend.

As a result, Southend Coastguard has re-iterated nobody should venture onto the harbour for any reason.

Jeremy Littlewood, station manager for the coastguard, said: “There has been a rise recently, it has become a hotspot. It’s quite visible, a lot of people are curious as to what’s there.

“If people are to ignore advice, they need to check the tide times.

“The gulleys, which stretch from between 50 to 100 metres, can fill up quickly from knee height up to swimming territory.

“It is similar to tombstoning where you’re diving into shallow water.”