An Iraqi man was hauled off a flight to London after a fellow passenger thought she saw extremist messages on his mobile phone.
The easyJet flight from Vienna to Gatwick was grounded for several hours after the woman told authorities she saw messages relating to Islamic State.
All passengers had to disembark the plane as luggage was searched after the woman raised the alarm yesterday.
The plane then took off after a delay of around three hours, but both the man and the woman in question were held for further questioning.
The man has subsequently been released, the AFP news agency reported.
Austrian interior ministry spokesman Karl-Heinz Grundboeck told AFP: “There was nothing suspicious found and he has been allowed to continue his journey.
“The only thing outstanding is a detailed analysis of his mobile phone.”
The incident happened on board flight EZY5352, which was due to leave Vienna International Airport at 12pm local time, landing at Gatwick two hours later.
The nationality of the woman involved in the incident on the Airbus A319 is not clear.
An easyJet spokeswoman told the MailOnline: “EasyJet can confirm that flight EZY5352 from Vienna to London Gatwick was delayed due to additional security checks before departure.
“The safety and security of its passengers and crew is our highest priority.
“We apologise for the delay and any inconvenience caused as a result.”
The Evening Standard has contacted easyJet for further comment.
European transport hubs have seen heightened security in recent days after 31 people were killed in terror attacks at Brussels airport and one of the city’s Metro stations.