The Australian Broadcasting Corp. said it is unknown if the incident was deliberate or accidental.
Police, ambulance and fire vehicles responded to the scene.
The bomb squad will also inspect the vehicle, which is wedged between two of the gate's vertical posts, to make sure it can be removed safely.
Roads surrounding the embassy have been closed.
Embassy officials have also been turned away from the scene and are unable to return to their residences, ABC reported.
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