Just days before the 30th anniversary of the crackdown on a pro-democracy demonstration in Tiananmen Square on June 4, Twitter suspended a large number of accounts, including those belonging to Chinese political commentators, the media reported.

Twitter later apologised for the error.

Twitter’s action, which affected more than 100 users, came over several hours late Friday and early Saturday, The New York Times reported citing a human rights worker. As a result, accounts of several human rights lawyers, activists and students, among others, got suspended.

“Among the accounts suspended are some prominent, long-time Chinese-language tweeps: @Sasha_Gong, @wmeng8. Both live in the US. More accts have been suspended than I can keep up,” wrote one user.

Twitter said the accounts it suspended “as part of its work to protect the health of the public conversation” were not mass reported by the Chinese authorities.

“Sometimes our routine actions catch false positives or we make errors. We apologise. We’re working to ensure we overturn any errors, but we remain vigilant in enforcing our rules for those who violate them. As always, account holders can appeal,” Twitter said in a statement.