NICHOLAS KAMM/AFP/Getty Images
(USA Today)-- Yahoo on Thursday said it reset passwords on many Yahoo Mail accounts after identifying "a coordinated effort" to gain unauthorized access.
It said usernames and passwords of its email customers were used to access accounts. It did not say how many accounts were affected.
"The information sought in the attack seems to be names and email addresses from the affected accounts' most recent sent emails," the company said in a blog post.
Yahoo says it believes the usernames and passwords weren't collected from its own systems, but from a third-party database.
The company says it is resetting passwords on affected accounts and has "implemented additional measures" to block further attacks.
The company would not comment beyond the information in its blog post. It says it is working with federal law enforcement.
The blog post also reminds users on best practices: Change passwords regularly, use strong variations on numbers and symbols and vary passwords across websites and services.
Yahoo has security teams focused on hacking attempts as the tech giant was breached multiple times in 2013. The most visible: a website hack in which 400 million Yahoo users account were accessed. The company subsequently began using more secure HTTPS web address. But the hacking attempts haven't stopped.
You may also like...
Arrrrrr! Pirates invade Tampa for Gasparilla
Treason? Secret Service visits candidate who says Obama should hang
Mystery House: Unsuspecting house holds a hidden secret
Abuse Arrest: Hog-hunting mom leaves kids in freezing car
Seeking Sasquatch: Bigfoot sightings abound in Colorado
Cyclist stuck in windshield: "Hi, I'm the guy you hit"
Miracle Baby: Tampa toddler has 5-organ transplant
Here kitty, kitty: Lion escapes enclosure at Pasco sanctuary
#ShortYellows: Florida quietly shortened yellow lights
Kittens shot: Officer shoots kittens in front of children
Popular photo galleries:
Faces of Meth: Devastating before and after photos of meth abusers
Trayvon Martin Shooting: Trayvon Martin crime scene photos and George Zimmerman injury photos
Hooters Winners: Winners of the 2013 Hooters swimsuit pageant
Rejected: Funny Florida license plates rejected by the DMV***warning graphic***
Deadly sinkhole: Home collapses, man dies in giant sinkhole
Florida Sex Offenders: Look up sex offenders in any Florida neighborhood here
Restaurant Inspections: Look up inspection reports for any Florida restaurant here