By Raphael Satter and Christopher Bing
WASHINGTON (Reuters) - An outage at a unit of the UnitedHealth Group that has led to nationwide disruptions in the filling of prescriptions for days was triggered by a ransomware group dubbed "Blackcat," two sources familiar with the matter told Reuters.
The group, which is also known as "ALPHV" and "Noberus," has previously terrorized major businesses including MGM Resorts International and Caesars Entertainment.
(Reporting by Raphael Satter; Editing by Chizu Nomiyama)