An Oscar-nominated documentary film shows the heroic efforts of the Greek Coastguard to rescue some of the 600,000 refugees attempting to cross the 4.1-mile stretch of water between Turkey and the Greek island of Lesbos from 2015 to 2016.

The 21-minute film, 4.1 Miles (embedded below), is an uncomfortable and at times deeply distressing watch.

“The world needs to know what’s happening here,” laments one of the rescuers, after failing to resuscitate a seven-year-old child. “We can’t be going through this alone.”

“There are no words to describe how I feel. It’s a nightmare,” he adds. “They come from war. They escape the bombs that fall on their homes and we see these families in the Greek sea… losing each other in the Greek sea. In the sea of a peaceful country… because of the way they have to cross.”

Record numbers of refugees continue their desperate attempts to reach Europe – many fleeing war and persecution in their home countries in the Middle East and Africa. The hundreds and thousands who have reached Lesbos represent just a fraction of the on-going crisis.