OTTAWA — An internal audit says better oversight, training, and detection technology are needed to keep illicit drugs and other contraband from slipping into the country in air cargo.

The Canada Border Services Agency audit says the findings are significant because commercial air cargo accounts for about one-quarter of all arriving shipments.

The auditors say there is no national electronic system for recording the results of aircraft examinations.

In addition, the availability and usefulness of tools to help with examinations vary across the country.

The audit, dated last July, was only recently made public.

Portions of the document were considered too sensitive to release.

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