The ghost ships in the English Channel and the question of what to do about them

The email, purportedly written on behalf of five colleagues aboard the tanker sailing under the name Beeta, contained a litany of complaints: crew members, it was alleged, had not been paid and were being treated "like animals"; and provisions were running low. The staff in Mumbai worked for the International Transport Workers Federation (ITF), the world's leading organisation representing seafarers, and were used to dealing with complaints from all corners of the globe. But what caught their eye was the fact that the emails hadn't just been copied to multiple ITF offices, but also to sanctions enforcement bodies in several countries. "The vessel is sanctioned and blacklisted," the sailor wrote. He said he had discovered that the vessel calling itself the Beeta was in fact an American-sanctioned tanker called the Gale. The sailor and his colleagues were desperate to leave. "I've been at sea for many years," he told the BBC when we contacted him. "I know what's right and wrong." Inadvertently, the crew member had found himself involved in a problem at the heart of some of today's most contentious geopolitical issues: a surging number of tankers, transporting Russian and Iranian oil, operating outside maritime rules, using a variety of methods to conceal their identities. This "shadow fleet", as it's known, is growing fast.