Terrorists and dangerous criminals were potentially among millions of foreigners allowed into Europe without facing proper checks, a damning report has found.

More than half of the 951 border guards interviewed admitted they allow people into the EU's Schengen area without running proper checks.

Delayed or defective IT systems took the brunt of the blame, with information about individuals either not uploaded quickly enough or not cross-referenced.

France, Germany, Italy, Spain and Greece issued nearly 18million visas between October 2015 and September 2017 but only carried out 14million checks, the report found.

More than half of the 951 border guards interviewed admitted they allow people into the EU's Schengen area without running proper checks

Delayed or defective IT systems took the brunt of the blame, with information about individuals either not uploaded quickly enough or not cross-referenced

Non-EU foreigners have to apply for visas in order to be allowed into the Schengen area, which has no internal borders. It comprises 26 states, but not the UK and Ireland.

The report by the European Court of Auditors examined five IT systems into which Brussels has ploughed around £600million to try to strengthen the EU's external borders. But it found that data available to border guards was patchy.

Inspectors also found that only ten member states could properly access the system holding biometric data such as fingerprints.

And France does not cross-reference the Passenger Names Record (PNR) system from flights entering the bloc with the Schengen Information System (SIS), which holds details of terrorists and other criminals.

The report found: 'In practice, this means that when checking passenger lists for suspected terrorists, France only uses information from its national databases.

If there is an alert on a suspect in SIS, and that suspect is known to other European authorities but not to the French, their PNR check will not detect that person.'