Australia’s leading cybersecurity agency is investigating a breach of the federal parliamentary computing network amid speculation of hacking by a foreign nation. Lawmakers and staff in the capital, Canberra, were made to change their passwords on the system after the overnight breach, AP reported. House of Representatives Speaker Tony Smith and Senate President Scott Ryan say there’s no evidence that data had been accessed in the breach. Australian officials have not blamed any country. In 2011, it was reported that China was suspected of accessing the email system used by lawmakers and parliamentary staff. Cybersecurity expert Fergus Hanson of the Australian Strategic Policy Institute said it’s likely a “nation-state” was behind the incident.