Details from distant Essex are still rather sketchy; suffice it to register that it has been a horrendous tragedy. Thirty-nine people died inside a lorry, and it has been established that they were all Chinese nationals. The deaths have thrown up the larger issue of the global migrant crisis. The victims arrived in Britain from Belgium by sea, in a refrigerated container, shortly after midnight on Wednesday morning. The container was then attached to the back of a lorry that had come from Northern Ireland via Holyhead and was driven to an industrial estate in Essex, where it was discovered about an hour later.

There were no survivors. On the face of it, it was a well coordinated transportation strategy that alas has now turned out to be mortal. Certain fundamental questions need to be asked and answered in course of the investigation that is under way. Who were the victims? Did they enter the lorry container willingly or under duress? Who was responsible for loading them into the container? By what route did they reach Essex? Were they being trafficked or were they migrants entering the country illegally?

Answers to these questions are essential if a humanitarian tragedy is seriously to be probed in order to get to the bottom of what has been called a case of mass murder. Ergo, an international response is direly imperative. Smuggling is now an integral part of the new global economy. According to the International Organization for Migration’s missing migrants project, more than 4,000 people have died or have gone missing on migratory routes around the world for each of the last five years. In 2000, 58 Chinese people were found dead in Dover in a truck that had travelled, like the one last week, from Zeebrugge in Belgium. They had died of suffocation after the container’s only air vent had been closed to lessen the chance of detection.

In 2014, 35 men, women and children were discovered “near to death” in a container at Tilbury. The latest tragedy has happened in spite of better detection methods and greater official alertness. Many drivers are more thoroughly trained to conduct regular walk-around checks to detect tampering. But improvements at ports like Calais may have diverted people-smugglers to less tightly monitored ports such as Zeebrugge.

Refrigerated containers, unimaginable though this is in human terms, are being used as these are more effectively sealed from scrutiny. Better detection technology and adequate levels of personnel are certainly important. So is effective punishment for the people-traffickers and smugglers. Rightly has it been contended in Britain that global migration cannot be controlled merely by raising the drawbridge at the white cliffs of Dover. This is an international problem, one that calls for international action.

Migratory pressures are encouraging millions to make long and dangerous journeys to escape suffering and poverty and to seek safer and better lives in countries like Britain. Maybe the policy of blocking the borders calls for reflection not the least because the migrants are prepared to clamber onto refrigerated containers to get across that border.