A call centre on Wearside was evacuated after a suspicious package was discovered.
Workers at npower at Rainton Bridge, in Houghton, were told to get out of the Cygnet Way site this morning.
A number of police officers arrived at the scene after they were called shortly before 10am, with a bomb disposal unit also arriving.
However, hours later bosses at npower later said that after work by the emergency services, the package "did not pose a danger".
A worker who spoke to the Echo said: "Everyone has been evacuated because of a suspicious package.
"There was a fire alarm and we had to get out.
"Police are all over. A lot of people are panicking."
Another worker has said that all staff have been told to go to nearby Rainton Meadows Arena in the meantime.
A spokeswoman for npower said: "We can confirm that a suspicious package was discovered on site this morning.
"The building was immediately evacuated and the appropriate emergency services were called but have confirmed that the package does not pose a danger to anyone.
"The safety of our staff is our absolute priority and we would like to thank the emergency services for their swift response to the situation."
A spokesman for Northumbria Police said: "Following a report of a suspicious package at npower in Cygnet Way, police have investigated the incident and further enquiries have found the item not to pose any risk to the public.
"Police have thanked those affected for their cooperation and patience."