A BOMB squad is attending a Twin Waters business after staff members were sprayed with a possible poisonous substance and a suspicious device was left on the counter.
Around 1pm a man dressed in a white protective jumpsuit and wearing a face mask entered the Ocean Dr pharmacy and threatened staff.
He sprayed a number of staff members with an unknown substance before he fled the scene with a quantity of drugs.
A Queensland Fire spokesperson said that they have decontaminated three people and that they were in the hands of the Queensland Ambulance Service.
Three women aged 19, 24 and 32 were later taken to Nambour Hospital for observation after being sprayed with the chemicals.
A Queensland Ambulance spokesperson said that they have transported one patient in a stable condition to Nambour hospital.
Queensland Fire currently has five crews on scene with a sixth on the way and will be getting scientific officers to do testing on the area.
The building where the incident happened and the opposite buildings have been evacuated by police.
The man is described as being in his 40s, Caucasian in appearance, of a slim build with grey brown hair.
Anyone with information which could assist with this matter should contact Crime Stoppers anonymously via 1800 333 000 or crimestoppers.com.au 24hrs a day.