In recent days, calming seas in the Mediterranean have seen a huge rise in the number of people attempting the perilous crossing from north Africa to Europe. Aid agencies have rescued thousands of the migrants and refugees who have been crammed on to often barely seaworthy boats run by smugglers and criminal gangs.

For the last few days, our team have been on a German rescue vessel on that central route, just off the Libyan coast. A warning: this report contains images that you may find distressing.