Manchester United have conducted forensic investigations following a cyber attack on the Premier League club's systems and are working with the National Cyber Security Centre (NCSC) to assess the damage.
United said last week they had experienced a cyber attack and had shut down affected systems to protect data, though club media channels, including the website and mobile app, were unaffected.
"The NCSC is aware of an incident affecting Manchester United Football Club and we are working with the organisation and partners to understand impact," a spokesperson for the security agency was quoted as saying by British media.
United said the attack had not impacted matchday operations.
"Following the recent cyberattack on the club, our IT team and external experts secured our networks and have conducted forensic investigations," United said in a statement.
"This attack was by nature disruptive, but we are not aware of any fan data being compromised. Critical systems required for matches at Old Trafford remained secure and games have gone ahead as normal."
The club said it would not comment on those responsible for the attack.
United face Southampton in the Premier League on Sunday.
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