KECSKEMET, Hungary (Reuters) - People-smugglers ignored the cries of 71 migrants as they suffocated in the back of a truck, then dumped it, crammed with corpses, at the side of an Austrian motorway, a murder trial heard on Wednesday.

Defendants stand in the court room, ahead of the trial in which they are charged with causing the death of 71 migrants who suffocated in a lorry found beside an Austrian motorway in 2015, in Kecskemet, Hungary June 21, 2017. REUTERS/Bernadett Szabo

Four men are charged with the killings of the 71 men, women and children at the height of Europe’s migrant crisis in 2015. They and seven others are also charged with the smuggling of hundreds of people across Europe.

The one Afghan and three Bulgarians facing murder charges were led into the Hungarian courtroom in handcuffs by armed police wearing face masks on the opening day of their trial.

The bearded Afghan man, named as Lahoo Samsooryamal and described as leader of the smuggling gang, smiled at the media as he entered. He carried a folder in his hands bearing the words “Allahu Akbar” (God is Great).

The bodies of the 59 men, eight women and four children, from Syria, Iraq and Afghanistan, were found inside the abandoned truck on August 26, 2015.

“The 71 victims, due to the small space, inability to move, a lack of air and overheating ... died shortly after they set off on the journey,” the Kecskemet court said in a statement posted on its website before the hearing.

“Before their deaths they continuously banged on the sides of the lorry and shouted.”

The deaths shocked Europe as it struggled to cope with the massive influx of migrants. It was the worst incident of its kind on the route across the Balkans taken by hundreds of thousands fleeing war and poverty in the Middle East, Africa and Asia.

Prosecutor Gabor Schmidt spoke for five hours in court on Wednesday, listing 26 counts of people-smuggling, with the journey in which the 71 died as one of the last cases.

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He said that as the migrant crisis peaked in 2015, the defendants stepped up their operation to maximize profits, taking up to 100 people a day from Hungary to Austria or Germany, mostly along the M1 motorway connecting Budapest with Vienna.

Before the August incident, the defendants had carried many migrants in similar conditions, causing “significant physical and mental suffering”, the prosecutor said.

CRIES CEASED

Schmidt said the Afghan defendant had promised to pay 3,500 euros to one of the Bulgarian defendants to drive the Volvo freezer truck from the Serbian-Hungarian border to Germany.

The 71 migrants were carried in the back of the unventilated vehicle, whose doors could not be opened from inside. The three others in the smuggling gang followed the truck in cars, and were in phone contact during the journey.

The migrants started banging on the sides of the vehicle and shouting 30-40 minutes after departure.

Schmidt said the driver of the truck repeatedly told his Afghan boss about the cries for help, but was told not to stop to open the doors. He obeyed.

“The defendants were aware that the people inside the Volvo were shouting and banging ... because they could not breathe,” the prosecutor told the court.

“And they were also aware that there were children inside.”

The migrants tried to remove rubber insulation and smash holes in the side of the vehicle.

The prosecutor said the Afghan had told one of the other defendants by phone that “he wanted the victims to die” and that if they did, the bodies should be dumped later.

The gang stopped twice to check the engine’s coolant water and refuel, but did not open the doors.

At one stop, no more shouting could be heard. The convoy drove across to Austria and abandoned the vehicle near Parndorf.

“They were aware that the victims locked up inside the lorry would suffocate unless let out,” the prosecutor said.

“All victims ... died within three hours, at the latest, after the start of the journey.”

The four defendants are also charged with smuggling other migrants over several months.

Seven other men are charged only with smuggling. Only six of the seven, who are all Bulgarians, appeared in court in the Hungarian city of Kecskemet. Authorities said one was still on the run.