[Note: undated footage]

A group of schoolchildren ventured onto an ice floe and became stranded away from the shore in Vladivostok, Russia. The children saved themselves without waiting for rescuers.

Horrified witnesses called the emergency services when they spotted the youngsters walking far out to sea in Vadivostok's Golden Horn Bay.

Video footage of the five pals shows one of them apparently collapsed while two of them try to pick him up more than 100 feet out from Sportivnaya Harbour.

But when rescuers arrived the friends had vanished after witnesses said they had got back to land unaided.

The local Deputy Head of Administration, Dmitry Svitailo, said: "No children were found on the ice floe. According to eyewitnesses, the children left the ice on their own."

Local media warned that temperatures have risen in Vladivostok by five degrees Celsius this week meaning that ice in the bay is starting to thaw and break up.