UPDATE: Gladstone State High School to open despite threats
8.36PM: GLADSTONE State High School has moved to dispel rumours school will be cancelled tomorrow, following the third bomb threat and subsequent evacuation of classrooms in as many school days.
Students were taken to a secure area this afternoon during the incident, where they were provided with bottled water, sunscreen and access to toilets.
They were released at about 1.45pm on the advice of police before classes resumed later in the day.
A message posted on the school's Facebook page confirmed the school would be open and ready for business.
Principal Garry Goltz also wrote to parents and caregivers late this afternoon, saying the entire school community was feeling the frustration of three evacuations in three school days.
"But, as previously stated, we refuse to compromise on the safety of our students," Mr Goltz said.
"The Queensland Police Service will continue to investigate these threats and will keep us informed as the investigations continue."
1.48PM: GLADSTONE State High School has released a statement describing the situation as a "precautionary evacuation task".
"Unfortunately, we are experiencing a similar situation as we did last Thursday and last Friday," the statement said.
"Consequently, there is currently a precautionary evacuation taking place.
"While the staff are feeling as frustrated as (you) are to be in this predicament again, the safety of the students and all others on site remains our paramount priority, and we refuse to compromise in this area.
"We thank our students at the maturity and co-operation they are displaying while we continue to work with emergency services.
"More information to parents will be communicated when we are in a position to do so."
EARLIER: BOMB squad crews have been called to Gladstone State High School after another suspicious note was reportedly found in a bathroom this morning.
It is the third suspected bomb threat at the high school in less than a week - one for each school day since last Thursday.
Classrooms at the school have been evacuated and a loud alarm is sounding across the school grounds.
Queensland Police Service confirmed crews were investigating the situation after a note was found in the toilet block.
A spokesman said police had been called at 12.30pm and sent two crews to the school to investigate.
Similar incidents occurred at the school last Thursday and Friday.
Classrooms at Toolooa State High School were also evacuated last Tuesday under similar circumstances.