A Cypriot student is facing a possible jail term after admitting taking eight explosive flares on to a plane at Stansted Airport and possessing a terrorist manual.
22-year-old Andreas Pierides from Finchley, London was stopped on the gangway as he was about to board a flight to Cyprus on 15 May.
Police were alerted to Pierides after a member of the public spotted him on a train reading an electronic publication with instructions on how to make a car bomb on 19 January.
As they arrested him, officers seized a box of distress signal mini-flares which they found inside luggage which had already been stowed on the plane, a court heard.
But they handed them back in error after Pierides was charged for having a terrorist manual.
Five days later, police went to his bail address in north London to ask for the flares back and arrest him again, this time under the Aviation Security Act 1982.
At a hearing at the Old Bailey, Pierides pleaded guilty to a charge under the 2000 Terrorism Act of possessing an electronic version of the Anarchist Cookbook, he also admitted having a dangerous article in an airport.
The judge Mr Justice Sweeney ordered a pre-sentence report and adjourned sentencing to 27 October.
More top news
Dry with some sunshine but a cold wind.
A year after the tidal surge the Suffolk village of Waldringfield has new flood defences in place
There'll be long spells of sunshine in many places during Saturday before it turns cloudier and windier on Sunday.