BT, the UK-based telecom, has pulled its 6 million users off Yahoo Mail after 10 years.

The company announced the move on Thursday. The company didn't give a reason for the move, but The Telegraph reports that BT users have been complaining in recent months about hacking attacks and spam. In March, BT began investigating the complaints, according to the publication. The Next Web also reported that Yahoo Mail had a wave of hack attacks earlier this year. In addition to losing Yahoo Mail, the BT will close its Yahoo portal site.

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Yahoo reps could not be reached for immediate comment on the report. Yahoo Mail claimed 281 million global users as of last year, and though 6 million is only about 2% of that figure, the move comes at a tricky time for Yahoo in which CEO Marissa Mayer (pictured above) is attempting to redefine the company as a relevant player. The news also comes as Yahoo Mail's biggest rival — Google's Gmail — introduced an upgrade this week.

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