https://www.reuters.com/article/us-twitter-results/twitter-warns-fake-account-purge-to-keep-erasing-users-shares-drop-19-percent-idUSKBN1KH17X >Twitter Inc on Friday said it lost 1 million monthly active users from the previous quarter and warned the closely watched figure could keep falling as it deletes more phony accounts, causing the biggest one-day decline in its shares since 2016.