Officials in Austria said Friday that they now believe that the decomposing bodies of 71 migrants were in a truck that was found by the side of the road in Burgenland Thursday. It is believed that the migrants were from Syria.

On Thursday, police said that there could have been anywhere between 20 and 50 bodies in the truck and that they had already started decomposing. However, during a press conference on Friday, they said it was much worse than initially believed.

According to the New York Times, police said there were the bodies of 59 men, eight women, three young boys and a girl. They found a Syrian passport on one of the victims.

It’s still not clear when the migrants died, reports The Wall Street Journal. Police said that suffocation is the likely cause of death, but other means can’t be dismissed at this time. Investigators estimate that they may have been dead for up to two days before the truck was discovered.

The truck had Hungarian license plates and the logos of a Slovakian poultry company, which has said that it did noes not currently own the truck.

Hungarian police have arrested three people linked to human trafficking, including the truck owner and two drivers.

The incident only serves to highlight the growing migrant crisis in Europe, as more and more refugees flee conflicts in Afghanistan, Syria and Iraq. Europe is seeing the largest wave of migrants since World War II, with the UN estimating that 3,000 people try to enter Europe through the Balkans daily.

screenshot from Reuters YouTube video