PSP police evacuated the Lisbon offices of telecommunications operator NOS yesterday after receiving an anonymous email saying a bomb would go off at 2pm.
The building was sealed off for four hours from midday as security personnel swept it from top to bottom.
According to jornal i website, bomb squad officers were not called as no device was found.
The alert came through just before midday, and police are thought to be trying to discover the source of the mystery email.
Coincidentally perhaps, the bomb threat came in a week in which internet hackers targeted a number of State-run websites, including that of the Bank of Portugal, the Ministry of Agriculture and Águas de Portugal.
