Instagram removed the account of prominent vaccine skeptic Robert F. Kennedy Jr., one of the highest-profile steps in parent company Facebook Inc.’s intensifying effort to combat false and misleading information about Covid-19.

An Instagram spokeswoman said Wednesday that the company permanently removed the account “for repeatedly sharing debunked claims about the coronavirus or vaccines.” Mr. Kennedy had more than 800,000 followers on Instagram before the account was closed, according to the company.

As of late Wednesday, Mr. Kennedy’s Facebook page, which has more than 300,000 followers, was still up.

Mr. Kennedy couldn’t immediately be reached for comment late Wednesday. His Twitter account, which has some 214,000 followers and where he also frequently criticizes vaccines, also remained up as of Wednesday night.

Facebook earlier this week said it was stepping up efforts to remove false statements related to Covid-19, Covid vaccines and vaccines in general on both its flagship platform and Instagram. The company said a longer list of claims deemed false by leading health authorities—including that vaccines are ineffective and more dangerous than contracting the targeted disease—would be subject to removal.