Glasgow-born Aqsa Mahmood abandoned a university course last year to join Islamic State fighters in Syria.
Since then she has married and was found as the one behind social media messages encouraging fellow fanatics to plan terror attacks in Britain. She is the daughter of a successful Pakistani business man settled in Scotland.
She has posted regular messages on Twitter, ranging from descriptions of daily life to publicising propaganda asking people to commit atrocities in the West, the Evening Standard reported today.
In one message in June she called for fanatics to copy the murder of soldier Lee Rigby, stabbed to death on a London street last year, the Boston Marathon bombing and the killings carried out by a soldier at the Fort Hood US army base in Texas.
She said: "Follow the examples of your brothers from Woolwich, Texas and Boston. If you cannot make it to the battlefield, then bring the battlefield to yourself".
Scottish police and the security services have confirmed they are aware of Mahmood but herinvolvement with radical Islam and her decision to travel to Syria has shocked family and friends, the report said.
A Scotland police spokesperson said: "A 19-year-old female from Scotland was reported missing to us by her family in November 2013. Inquiries are ongoing in relation to her whereabouts and we are supporting her family."
Mahmood is one of up to 500 British citizens, mainly men, believed to have travelled to Syria to join ISIS.
British Prime Minister David Cameron had unveiled new tougher measures in the House of Commons on Monday to tackle the issue of British citizens travelling to warzones and bringing terror to the streets of the UK.
Police will be given new powers to confiscate passports of suspects and a temporary ban on re-entry into the UK from a warzone are being finalised.