https://www.theguardian.com/world/2017/oct/09/russian-operatives-spent-thousands-of-dollars-on-google-ads-source-claims

As congressional investigations deepen, an anonymous source at the company tells Reuters that ads were purchased in order to meddle in the 2016 election

Google has discovered Russian operatives spent tens of thousands of dollars on ads on its YouTube, Gmail and Google Search products in an effort to meddle in the 2016 US presidential election, a person briefed on the company’s investigation told Reuters on Monday.