WASHINGTON, July 19 (Reuters) - U.S. President Joe Biden took a softer tone when talking about Facebook Inc on Monday, after saying last week that the social media company was "killing people" by allowing the spread of misinformation about vaccines against the coronavirus.

Biden told reporters on Monday that he was hoping Facebook would "look in the mirror."

"My hope is, that Facebook, instead of taking it personally that ... they would do something about the misinformation," the president said. "Think about misinformation going to your son, your daughter, your, your relatives, someone you love."

COVID-19 misinformation has spread during the pandemic on social media sites including Facebook, Twitter and Alphabet Inc-owned YouTube. Researchers and lawmakers have long accused Facebook of failing to police harmful content on its platforms.

When asked on Friday about his message to social media platforms, Biden responded: "They're killing people. ... Look, the only pandemic we have is among the unvaccinated. And they're killing people."

Facebook responded sharply last week, saying that 85% of Facebook users were vaccinated or wanted to be. "President Biden’s goal was for 70% of Americans to be vaccinated by July 4. Facebook is not the reason this goal was missed," Facebook said in a corporate blog post by Guy Rosen, a company vice president.

The company has introduced rules against making specific false claims about COVID-19 and vaccines to prevent the illness, and says it provides people with reliable information on these topics. (Reporting by Steve Holland; Writing by Diane Bartz; Editing by Bill Berkrot)