A truck has spilt 20 litres of an unknown chemical onto Leach Highway, causing traffic delays.
Emergency services crews are at the scene in Kewdale clearing the chemicals from the eastbound lanes.
The incident happened near the Tonkin Highway intersection about 11am.
A Fire and Emergency Services Authority spokeswoman said a container had fallen from a truck in the middle of the highway.
She said the chemicals were not toxic.Motorists are advised to avoid the area if possible.
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