Google plans to add words such as “gun-grips” and “scopes and sights” to its list of prohibited AdWords later this month.

The web giant’s AdWords is an online service that allows advertisers to place search results for their websites on a search engine results page. The advertiser chooses keywords that a searcher might use on Google, then creates an advertisement that will appear the page when the keywords are used.

Breitbart News reported the search engine announced in an email it will also ban any AdWords that related to “3D printing of guns or gun parts,” which will include “instructions” on 3D printing of firearm parts.

The email provides a “non-exhaustive list of examples of products for which ads will no longer be allowed.”

Other words are “stocks,” “conversion kits,” and “tripods and bipods”

YouTube, which is owned by Google’s parent company, already has been banned all gun demonstration videos.

Facebook has implemented incremental prohibitions on gun ads and sales.

Second Amendment Foundation executive director Alan Gottlieb told Breitbart News the “backdoor gun control” by Google is “a direct attack on gun ownership.”

“Maybe it is time to regulate the internet giants like Google, Facebook, and YouTube and not gun ownership,” he said.

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