Facebook said Wednesday that it was removing a series of ads from President Trump's campaign that linked American acceptance of refugees with increased coronavirus risk, a connection Facebook says is without merit.

Why it matters: The ads were pulled after they received thousands of impressions and are a sign that the Trump campaign continues to test the limits of social media rules on false information.

“We rejected these ads because we don’t allow claims that people’s physical safety, health, or survival is threatened by people on the basis of their national origin or immigration status,” Facebook spokesperson Andy Stone said in a statement.

The big picture: The move comes as the social media platforms prepare for an intense period through the November election and until the race is decided. Facebook said last week it wouldn't allow ads that prematurely declare victory and has also said it will stop allowing new political ads a week before Election Day.

• On Wednesday, it said it was expanding its election-related policy to limit additional types of ads that could interfere with voting.

"We also won’t allow ads with content that seeks to delegitimize the outcome of an election," Facebook's Rob Leathern said in a series of tweets. "For example, this would include calling a method of voting inherently fraudulent or corrupt, or using isolated incidents of voter fraud to delegitimize the result of an election."

Yes, but: The new rules about voting content apply to ads on Facebook and Instagram. Facebook will not take down organic posts that contain such charges, but will label them.

Meanwhile: Twitter said it removed 130 accounts that it said appeared to be from Iran and were "attempting to disrupt the public conversation" during Tuesday's debate. The company said it acted on information provided by the FBI.