Police closed a section of Seddon St tonight when an officer conducting a traffic stop found that the car he'd pulled over contained substances suspected to be dangerous chemicals.

Fire and ambulance personnel were called to the scene, in Seddon St between between Wai-iti Rd and Rugby St in the Highfield neighbourhood, shortly after 5pm.

The substances were suspected to be hazardous chemicals that could ignite, according to Timaru police Senior Sergeant Mark Offen. Police wouldn't disclose the type of chemicals they suspected were present, except to say that they could possibly be used to manufacture drugs.

The driver, a young man believed to reside in Timaru, was the only occupant of the car, Mr Offen said.

Emergency personnel screened off an area and set up a decontamination shower on the opposite side of Seddon St from where the vehicle was parked, so that the driver could be cleansed as a precaution after being in close contact with the substances.

Senior fire officer Martyn Bennett said the police officer who'd conducted the traffic stop washed his hands and arms after coming into contact with the driver.

After an assessment of the scene ''we took advice from New Zealand Hazardous Substances that the best course of action was a quick wash,'' Mr Bennett said.

Police contacted staff in Wellington for advice on whether the car could be moved or the area would have to be evacuated, Mr Offen said. They were cleared to remove the car from the scene at about 7pm.

Officials said the chemicals posed no contamination threat to anyone in the area who had not come into direct contact with them.

- © Fairfax NZ News