Migration is the "Trojan wooden horse" of terrorism and the current lull in the migrant flow is only temporary, Hungary's prime minister said Tuesday

Prime Minister Viktor Orban, an early supporter of U.S. President Donald Trump, has ordered the reinforcement of fences on Hungary's southern borders to keep out migrants. Orban says the migrants, many of whom are Muslims, are a threat to Europe's Christian identity and culture.

Orban said the migration issue would remain as long as its causes in the countries of origin were not dealt with and its potential risks were not recognized.

"Migration is the Trojan wooden horse of terrorism," Orban said at a swearing-in ceremony for a new group of border guards, called "border hunters" by the government. "The people that come to us don't want to live according to our culture and customs but according to their own — at European standards of living."

Orban said the migration pressure on Hungary's borders would continue as millions of people were planning to come to Europe in hope of better lives.

"We are still, at this moment, under siege," Orban said. "The migration flow has only slowed but it is not over. We have gained time to strengthen our lines of defense."

As Orban was speaking to the 462 new border guards, lawmakers from his governing Fidesz party and the far-right Jobbik party approved new rules which further limit the rights of asylum seekers and give police more power to send migrants back to Serbia.

During a state of emergency due to migration, recently extended until Sept. 7, all asylum seekers will kept at camps built from shipping containers on the border with Serbia until a final decision is made on their asylum requests.

The decision is in line with Hungary's intention to close all other refugee reception centers around the country, some of which were shut last year.

Police will also be allowed to return to the Serbian border any migrants caught anywhere in the country who cannot prove their legal right to be in Hungary. Since July 5, only migrants found within 8 kilometers (miles) of the border could be sent back to Serbia.

The new legislation was strongly criticized by human rights advocates, who said asylum seekers' rights to legal assistance would be severely limited.

"There are hardly 400 asylum seekers in the country," said a statement issued by seven rights groups, including Amnesty International Hungary, the Hungarian Helsinki Committee and MigSzol, the Migrant Solidarity Group of Hungary. "The extension of the state of emergency only serves to maintain the xenophobic, fear-mongering propaganda."

The United Nations refugee agency said it was "deeply concerned" about the detention of asylum seekers.

"This new law violates Hungary's obligations under international and EU laws, and will have a terrible physical and psychological impact on women, children and men who have already greatly suffered," the UNHCR said in a statement. "The detention of refugees and asylum seekers can only be justified on a limited number of grounds, and only where it is necessary, reasonable and proportionate."

Hungary built fences on the Serbian and Croatian border in 2015. Some 400,000 migrants passed through Hungary that year before the fences were in place, most on their way to Germany and other destinations in Western Europe. A second, 150-kilometers (93 miles)-long fence on the Serbian border equipped with motion and heat sensors and other surveillance tools is planned to be completed by May 1.

While Orban has said often that Hungary will apply its Christian values to take in asylum seekers, very few achieve protection here and only around 16 a day are now allowed to apply for asylum at the border transit zones. Experts fear even fewer will be allowed to apply as the new rules are applied.

In 2016, Hungary accepted 425 asylum seekers, while registering 29,432 asylum claims. In 2015, 502 asylum seekers were granted protection. Germany took in 890,000 asylum seekers in 2015 and 280,000 in 2016.