Xbox Live appears to be back up this morning following a brief outage last night for which a hacker group claimed responsibility.

The outage, which lasted more than an hour, impacted both Xbox 360 and Xbox One users of Xbox Live. Consoles were responding with the 80151909 error code, which warns that an Xbox Live profile has failed to download.

Microsoft’s Xbox support site never appeared to indicate any issues with Xbox Live services or apps. But this morning, users are reporting that the service appears to be back up.

The hacker group Lizard Squad took to Twitter last night to claim responsibility for taking Xbox Live offline. The group, which describes itself as “kings” of distributed denial-of-service (DDoS) attacks, tweeted that it was preparing for a larger attack at Christmas on Xbox Live and that today was a “small dose of what’s to come.”

Earlier this year, the group claimed responsibility for a similar attack on Sony’s PlayStation Network, as well as denial-of-service attacks on individual online games like Grand Theft Auto 5, League of Legends, Destiny and more.