Alva Review-Courier -

LONDON (AP) — Yahoo is warning users of potentially malicious activity on their accounts between 2015 and 2016, the latest development in the internet company's investigation of a mega-breach that exposed 1 billion users' data several years ago.

Yahoo confirmed Wednesday that it was notifying users that their accounts had potentially been compromised but declined to say how many people were affected.

In a statement, Yahoo tied some of the potential compromises to what it has described as the "state-sponsored actor" responsible for the theft of private data from more than 1 billion user account...