Some 3,000 refugees have been turned away by the Austrian police over the past 20 days for being "untruthful" about their nationalities, an official says.

Austrian police spokesman Rainer Dionisio said this was all due to more controls over the border points with Slovenia from where thousands of refugees and asylum seekers cross into the country.

According to Dionisio, those claiming to have come from war-torn countries including Syria, Iraq and other flashpoints in the Middle East, were questioned to be checked for their accents.

He said among those who had made false claims and been turned back were Moroccans, Algerians and other nationals.

Meanwhile, an Austrian bar owner said on Wednesday she had banned "all asylum-seekers", sparking strong criticism from human rights groups.

Slamming the ban as racist, Austrian rights groups said this highlighted an important loophole in Austria's legal system.

"Inciting hatred against 'foreigners' is illegal, but using the term 'refugee' or 'asylum-seeker' in a discriminatory way is not an offence under current sedition laws," explained Christina Schaefer of the ZARA initiative, which provides legal support to victims of racist attacks.

"We've been lobbying for ages to get this changed as it can leave people very vulnerable," she told AFP.                            

Europe is facing an unprecedented influx of refugees fleeing conflict zones in North Africa and the Middle East, particularly Syria.

Many blame major European powers and the West in general for the exodus, saying their policies have led to a surge in terrorism and wars in those regions, which have forced more people out of their homes.

European officials are struggling to forge a united response to the record numbers of refugees.

According to figures released by the International Organization for Migration (IOM), more than one million refugees and asylum seekers reached Europe’s shores in 2015 alone.

Over 3,300 people have either died or gone missing in perilous journeys to the continent.