Switzerland's Federal Office of Communications was back on Twitter on Wednesday after a week of enforced silence which the social networking giant blamed on an error. "OFCOM has been unable to post tweets since September 28," it said Tuesday on its website. "Twitter has blocked OFCOM's four accounts without providing any explanation and has not responded to any of the office's requests for information." OFCOM's accounts, which tweet separately in three Swiss national languages -- German, French and Italian -- plus English, were up and running again on Wednesday. In the meantime it had been publishing information on its website or via press releases. When questioned, Twitter said an error had occurred, without giving further details. vog/rjm/bp