He undertook the trip alone without an escort boat to raise awareness of plastic pollution in the ocean.

She also arranged to have back-up monitors and medication in the escort boats.

Even the escort boats seemed briefly to have lost him.

They will be protected by eight escort boats, each of which will be manned by a dozen armed guards.

Backed by three escort boats and smeared in porpoise oil, he set off into the ebb tide at a steady breaststroke.