Hacking collective Anonymous took credit for a Twitter outage early Monday, just weeks after the same group claimed responsibility for a massive disruption that disabled a swath of sites across the Web.

Twitter was rendered inoperable for approximately 30 minutes, during which it was impossible to use the messaging service both online and on mobile devices. New World Hackers, the Anonymous sect that claimed responsibility for an attack on New Hampshire-based Internet firm Dyn in October, also claimed responsibility for the latest outage, saying in a message to the Washington Examiner, “Twitter outage was us.”