Target Corp. is taking a new tack to combat theft at self-checkout stations.

The retailer is adding a new technology at its self-checkout registers that uses cameras to detect items on scanners, alerting shoppers who leave anything unscanned, according to internal documents viewed by Bloomberg News.

The technology, called TruScan, is being rolled out to all stores this year, the documents said. It could help Target track shoppers "who repeatedly fail to scan their items even after being prompted," according to the documents.

Shoppers will get audio and visual cues when they don't scan items and the technology has been piloted in some stores in recent months, said people familiar with the matter, asking not to be identified discussing private information.

Minneapolis-based Target and other U.S. retailers have added weight sensors and cameras at self-checkout stations to enhance security and typically have store employees intervene when there are errors. Target's TruScan technology is meant to go beyond that in a move to reduce theft and product shortages.

Stores eagerly added self-checkout stations in recent decades, seeking to save labor costs. That thinking has been challenged in recent years as companies juggle with rising incidents of theft at the self-checkout registers by people who walk out without paying or use incorrect bar codes to check out. Operators have been responding by testing new technologies, assigning more staff or removing self-checkout stations, though these changes haven't solved operational challenges at the registers.

Target is upgrading self-checkout stations after its March announcement of purchase limits of 10 products at these registers. The company also said it plans to open more traditional checkout lanes that are staffed by employees.

Dollar General Inc. said last month that shrink — inventory loss due to theft, damage and other factors — is weighing on the business and that it would overhaul its fleet of self-checkout stations. It's removing them from more than 300 locations with the highest shrink rates and converting them to employee-assisted locations at about 9,000 stores.

Kroger Co. has said it's experienced more organized crime at self-checkout stations and that it is investing in technologies to prevent theft.