Hungary is doing everything it can to keep out unwanted migrants, in spite of strong opposition from other European countries and human rights groups.

On Monday, the Hungarian Defense Force started building a temporary wall along the Serbian border to curb what government agencies describe as an unprecedented flow of undocumented people coming into the country.

"A daily average of 1,000 illegal border crossers are arriving in Hungary, so illegal immigration has become a severe problem and its control a prominent task," said a joint statement from Hungary's interior and defense ministries.

An estimated 80,000 refugees and migrants have reached Hungary this year — up from 43,000 in 2014. The vast majority of whom are arriving via Serbia from Syria, Afghanistan, and Iraq. Many will request asylum in Hungary then move onto other European Union countries such as Sweden and Germany.

The wall, which is planned to be four meters high and 110 miles long and cost around $35 million, was announced by the far-right Hungarian government in June to swift criticism from Serbia and beyond. "Building walls is not the solution," Serbian Prime Minister Aleksander Vucic told Deutsche Welle. "I do not understand this decision and I intend to talk about the issue with our European Union partners."

German Chancellor Angela Merkel has said the wall "makes no sense." An EU spokesperson also condemned the wall, telling the Irish Times, "We have only recently taken down walls in Europe; we should not be putting them up."

The wall is another part of Hungary's recent efforts to crack down on asylum seekers. Last month, the parliament passed laws that give border officials new powers to reject migrants coming from countries in the Middle East, and new laws to detain migrants in temporary camps and block appeals of failed claims.

According to a recent report by Amnesty International, many migrants traveling through the Balkans experience abuse and violence by government officials and unscrupulous smugglers. The number of people arrested at the Serbian-Hungarian border has gone up more than 2500 percent since 2010. Amnesty criticizes Hungary's new anti-immigration measures, saying they will put more lives at risk.

"Refugees fleeing war and persecution make this journey across the Balkans in the hope of finding safety in Europe only to find themselves victims of abuse and exploitation and at the mercy of failing asylum systems," Amnesty International's deputy director Europe and central Asia told reporters last week.

"As increasing numbers of vulnerable refugees, asylum-seekers, and migrants become trapped in a Balkan no-man's land, the pressures on Serbia...are mounting."