Terrorists and criminals are "expected" to attempt to obtain Turkish passports in the hope of reaching Europe, taking advantaged of the visa-waiver deal between Turkey and the EU, the European Commission has warned.
The increased risk of an attack would come "as soon as" the programme kicks in and Turkish citizens are free to travel across Europe without visas, a European Commission report said.
The visa-waiver programme is part of a wider deal, in which Turkey agreed to take back migrants that entered the EU in exchange for sweeteners.
In exchange for each migrant returned, Turkey wanted the EU to accept one refugee, as well as incentivise the country by offering extra funding and early access to European visas.
The result is that 75m Turks would be able to enter the Schengen zone for up to 90 days at a time.
"The proposed visa liberalisation for Turkish citizens travelling to the EU could potentially have an impact on the terrorist risk in the EU in as far as the movement of terrorists of Turkish citizenship to and from the Schengen area is concerned," the Telegraph reported the European Commission report to have said.
"Suspect individuals being allowed to travel to the Schengen territory without the need to go through a visa request procedure would have a greater ability to enter the EU without being noticed."
"It can be expected that, as soon as Turkish citizens will obtain visa-free entry to the EU, foreign nationals will start trying to obtain Turkish passports in order to pretend to be Turkish citizens and enter the EU visa free, or use the identities of Turkish citizens, or to obtain by fraud the Turkish citizenship," the report said.
"This possibility may attract not only irregular migrants, but also criminals or terrorists."
Yesterday former head of MI6 Sir Richard Dearlove warned against a visa-waiver deal with Turkey. He said it was "perverse, like storing gasoline next to the fire we're trying to extinguish".