Payment service Venmo joined YouTube and Twitter on Wednesday in demanding that a facial recognition company stop harvesting user images to identify the people in them, which the startup does as part of its work with police.

Venmo said Wednesday it is sending a cease-and-desist letter to New York-based Clearview AI. The small firm has drawn scrutiny following investigative reports in January by the New York Times and Buzzfeed detailing its work with law enforcement agencies and its practice of scraping social media and other internet platforms for images.

"Scraping Venmo is a violation of our terms of service and we actively work to limit and block activity that violates these policies," said spokesman Justin Higgs, who said Wednesday the company is in the process of sending the letter.

Google-owned video service YouTube sent a similar letter to Clearview on Tuesday.

"YouTube's Terms of Service explicitly forbid collecting data that can be used to identify a person," YouTube spokesman Alex Joseph said in a statement Wednesday. "Clearview has publicly admitted to doing exactly that, and in response we sent them a cease and desist letter."

Twitter also sent a similar letter in January, according to the Times. CBS was first to report the YouTube letter Wednesday.

Clearview CEO Hoan Ton-That told CBS in an interview that it has a First Amendment right to the 3 billion images it has collected.

"The way we have built our system is to only take publicly available information and index it that way," he told CBS.

He also said the technology is only used by law enforcement to identify potential criminals. Clearview attorney Tor Ekeland said in a statement Wednesday that the company's technology "operates much in the same way as Google's search engine."