The driver overturned the vehicle as he tried to speed away from police at a border crossing, said Helmut Marban, police spokesman of Burgenland state. He had 20 people in his van, including four children.

Two men and a woman were killed in the crash, another seven people were seriously injured, and others sustained lighter injuries, he added.

The driver, thought to be of Russian origin, has been arrested, Marban told AFP. Investigators have so far managed to establish that some of those being smuggled in the van are of Syrian origin.

"The tragic death of three people... shows once again the brutality and unscrupulousness of the smuggling mafia," Interior Minister Gerhard Karner said in a statement.

His ministry announced in May that police had smashed a group believed to have smuggled tens of thousands of people, mostly Syrians, from neighbouring Hungary to Austria.

Investigations into the group started in early 2021. Two of those illegally transported across the border were found suffocated in a van last year.

In 2015, 71 people from Syria, Iraq and Afghanistan suffocated in the back of an air-tight van where they had been hidden by people smugglers.

The bodies, including three children and a baby, were discovered in Austria but they had died while still on the other side of the border with Hungary.