BUDAPEST, HUNGARY— The steady flow of migrants into Hungary from Serbia may come to a halt Tuesday.

Hungarian Prime Minister Victor Orban has promised tough action against anyone crossing the border illegally from that day onward. Doing so could mean three years in prison. Trying to cut the newly erected fence could mean five years.

Tensions Rise as Hungary Prepares to Bar Illegal Migrants

Anyone entering Hungary will have to file for asylum. But first they will have to prove they could not file for asylum in Serbia.

The Hungarian Helsinki Committee, a human rights advocacy group, has called this a “blanket authorization to reject 99 percent of asylum claims.”

The government has already moved several thousand soldiers to the border to bolster police already assigned there.

Meanwhile, volunteers helping the migrants say they will continue their work.

Tamas Lederer, founder of Migration Aid, said that in the history of his countrry, when humanity and the law have conflicted, Hungarians have chosen humanity.

No one knows exactly what will happen Tuesday. But in their own way, journalists, activists, migrants and the government are all preparing for the worst.