A prankster's use of smartphone technology to send a hoax bomb threat that forced a Gold Coast high school into lockdown may prove their undoing.
Queensland police are questioning several students from Palm Beach Currumbin State High School after separate bomb hoaxes twice forced the school into lockdown on Wednesday morning.
One, a 13-year-old boy, was cautioned after being dealt with under the Youth Justices Act on Wednesday afternoon, but police say he was not the main offender.
A day of drama was sparked when a cleaner discovered an envelope at the school's gate around 6am containing a white powder and a handwritten bomb threat on the back.
It's believed the message contained the words "enjoy the bomb".
Police and emergency services searched the school while parents were sent a text message advising them to keep students away until further notice.
Just before 9am the school was re-opened and Queensland Fire and Emergency Services crews confirmed the powder was simply flour.
An hour or so later another threat was received by several students and staff on iPhones via the AirDrop messaging service.
That threat sparked another lockdown with police again searching the property before an all-clear was given just before midday.
Police however say the AirDrop message has given them a good chance of identifying the perpetrator.
"AirDrop can only be successfully sent to other users within a very limited distance," Senior Sergeant Bill Lythgo told reporters.
"That allowed us to determine it was highly likely the threat was coming from within the school grounds."
Snr Sgt Lythgo said if the culprit was caught they would be prosecuted for their "extremely serious" conduct.
Police believe the same person who sent the AirDrop threat was responsible for delivering the envelope to the school around 5.20am.
The school is one of the largest on the Gold Coast with approximately 2500 students.
Parent Vicki Kelly, whose teenage daughters attend the school, said Wednesday's events had been stressful.
"It's a bit of a worry," Ms Kelly told News Corp Australia. "You wonder why someone would do something like this."
The school used its Facebook page to reassure parents that all was well.
"Please be reassured we are running classes as normal for the remainder of the school day and encourage students to stay at school," the statement read.
"Support will be offered to all students who may have experienced anxiety from this morning's incidents."
