Online-reviews firm Yelp Inc. alleged that Google is breaking a promise it made as part of a 2012 regulatory settlement to not scrape content from certain third-party sites including Yelp, escalating its yearslong battle against the search giant.

Yelp said in a letter late Sunday to Federal Trade Commission Chairwoman Maureen Ohlhausen that Google is using Yelp photos for local-business listings in its search results, despite Yelp’s formal request that Google not pull such content from its site.

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