Austria has diverted three of four lanes on the A13 motorway (Die Brennerautobahn) – 25 kilometres away from the Italian border – and has placed soldiers at a frontier railway station.
Hundreds of cars and trucks coming from Italy have been stopped and searched on the A13 motorway, according to a report in Italian daily Repubblica.
At least 15 soldiers are also on duty at Matrei am Brenner train station, checking passenger and cargo trains arriving from Italy, claims the daily.
It added that two women and six men, from West African nations Nigeria, Burkina Faso and Ivory Coast, were found alive hiding in the empty fuel tank of a train, normally reserved for liquified gas.
Austria recently announced it would send army back-up to help police its borders. The measures are in response to efforts by illegal migrants to enter Austria from Italy. Between 700 and 1,000 illegal immigrants are stopped in Tyrol every month, states a report in German newspaper zeit.de.
Yet official Austrian government statistics show that the number of asylum applications more than halved from 88,000 in 2015 to 42,000 in 2016.
"Surprising and unjustified"
The Italian government expressed its disappointment at Austria's military build-up on its shared border in early July, with Interior Minister Marco Minniti calling the move "surprising and unjustified".
The disappointment had little impact on the neighbour's decision-making process. "We must decide ourselves who enters our country and who doesn't," says Austrian Integration Minister Sebastian Kurz, cited in Austria's Der Standard daily.
"Migration to Austria is still at a level that is too high," said Minister Kurz in a statement released on Wednesday.
Austria had originally said there was no need for a hard border with Italy but appears to have u-turned recently in light of attempts by migrants to reach Austria from Italy via quieter border crossings.
Kurz had previously asked Italy to prevent migrants from reaching its mainland from Italian islands like Lampedusa, where many migrants and refugees first land in Europe.
"We hope that ferry services for illegal migrants will be halted between Italian islands like Lampedusa and the Italian mainland," Kurz said in July this year.
In 2015, Austria – like Germany – opened its borders to refugees fleeing conflicts in Syria, the Middle East and Central Asia, only to close them again in late 2016.
Austrian Interior Minister Wolfgang Sobotka however, careful to toe the EU's official line, says national borders can only exist within Schengen when other nations fail to secure their own borders.
"The removal of border controls within the Schengen area is justifiable for me only if the European external borders are adequately protected. As long as this does not succeed, there is no way of passing national measures," said Sobotka.
Earlier this month, The Local Italy reported that Austria had sent 70 soldiers to patrol the border with Italy in response to 16,000 asylum cases in the first half of 2017 and an apparent increase in the number of illegal migrants trying to reach Austria by rail and road from Italy.
Integration expert Kenan Küngör, cited in Austrian newspaper Der Standard, argues that Austria's new-found "pessimism" towards migration may be to do with having "not received the gratitude" it expected after opening its borders in 2015.
It is also to do with a "desire for control" in the face of "the future uncertainty surrounding migration," argues Küngör.
Other experts say Sobotka's Austrian People's Party is taking a more conservative stand on migration to keep out the far right in legislative elections expected on October 15th, 2017.
Meanwhile, the number of new migrant arrivals by sea from North Africa to Italy more than halved between June and July 2017, according to UNHCR data.
READ MORE: Road to Italy gets tougher for migrants