A man and woman have been charged after an explosive device "capable of causing injury" was allegedly found car parked at a Brisbane shopping centre.

The bomb squad was called to Redbank Plaza, south-west of Brisbane, after the suspicious device was found inside the vehicle about 9.15am, police said.

Officers arrived within 10 minutes to set up an exclusion zone.

The bomb squad was called to the car in Redbank Plaza at 9.15am. (AAP) (Supplied)

"It is capable of causing serious injury to people," Queensland Police Gareth James said.

"You would not want to be in close proximity to it."

Security cameras allegedly picked up a man and woman sitting in the car on the edge of the shopping centre carpark, with people monitoring the footage in nearby Ipswich raising the alarm with police.

A suspect device was found in the car, triggering the emergency warning. (9NEWS) (Supplied)

Once the exclusion zone had been set up, the bomb squad entered the car and found a cardboard box in the passenger side of the vehicle.

Inside the box was a glass jar containing a flammable liquid, a Halloween mask and other items, police said.

The device was dismantled, with the area declared safe by police about 11.35am.

The device has been dismantled and police are investigating the substance found inside the glass jar. (AAP) (Supplied)

A man and a woman are assisting police with inquiries. (9NEWS) (Supplied)

"It's really scary that it's happened close to the plaza," a local said.

Another said: "Wow ... you wouldn't think of that in this area."

The pair, a 37-year-old Camira man and 31-year-old Capalaba woman, were arrested at the scene.

The man has since been charged with a string of offences, including two counts of manufacturing an explosive without authority, and one count each of possessing dangerous goods, stealing, driving an uninsured vehicle and offences involving registration certificates.

The woman also faces a number of charges, including possessing dangerous goods, fraud, forgery and stealing.

A number of items were found in the vehicle which was purchased fraudulently, (AAP) (Supplied)

Both will appear in the Ipswich Magistrates Court tomorrow.

Police alleged the car was purchased with a fraudulent transaction just days ago.

A police spokesperson said the device was capable of causing "serious injury".

It is not known what the device inside the car is. (9NEWS) (Supplied)

"It was a fairly large glass jar which contained a substance," he said.

"I would suggest you would not want to be in close proximity to it."

Police said it was "more advanced" than a Molotov cocktail but disclosed few details as to the nature of the alleged device.

Queensland Police Commissioner Ian Stewart was informed of the situation. It is also understood he was aware of a potential attack.