Newly released figures show that over 4,000 migrants who came to Austria to claim asylum have gone underground and many have left for other more desirable countries in Europe.

By the end of August, there were an estimated 4,364 asylum seekers who have gone underground this year during their asylum process. Most of the asylum seekers are expected to have left the country to head to another country.

The number is a slight decrease from last year when 4,557 migrants went missing and in 2015 when the number peaked at 7,963, Der Standard reports.

So far this year, Austria has received 17,000 approved asylum applications – well below the limit set by the Austrian federal government last year of 37,500.

Many have credited the government’s stricter border controls for the decrease in the number of migrants arriving in the country. From January to May of this year, the government reported only 10,520 new arrivals.

The conservative Austrian People’s Party (ÖVP) has advocated cutting the migrant limit back even further to 17,000 per year. The anti-mass migration Freedom Party (FPÖ) has called for a reduction to zero migrants and want to focus on processing existing migrants and deporting failed asylum seekers.

In the latest polling before the Austrian national election on October 15th, the ÖVP and leader Sebastian Kurz have a healthy lead just ahead of the FPÖ who are pulling away from the Social Democrats who have lost much of their former support.

Austria has also been asked to take in more migrants by the European Union but ÖVP Interior Minister Wolfgang Sobotka has so far refused, pointing out that 90 per cent of asylum seekers end up on welfare programmes costing the Austrian taxpayer millions of euros.

The number of voluntary deportations has declined this year from 6,000 in 2016 to a projected 4,900 by the end of the year. The government has also increased the amount of cash given to migrants who voluntarily leave the country from €1,000 to €1,500.

Forced deportations have gone up dramatically with 4,642 cases by the end of August this year compared to 4,888 for the entire year of 2016.