IMP Aerospace and Defence near the Halifax Stanfield International Airport was locked down Thursday morning after the RCMP warned the company of a potential threat.
"We received a call from the RCMP approximately around 2 a.m. notifying us of a potential threat to the safety and or security of our facilities and potentially its employees," said Tom Galley, the executive vice-president of IMP Aerospace and Defence.
Galley would not describe the nature of the threat because of the police investigation.
About 11 people were working at the IMP facility overnight.
"We secured the facility, notified the employees therein, made sure that they were safe and told them to remain in the facility while the activities were going on outside," said Galley.
"That was the safest place to be."
Once daylight came, those employees evacuated the building.
IMP Aerospace and Defence also notified its hundreds of daytime staff not to come into work and the company's entire facility was shut down.
Galley said everything the company did was meant to protect its workers.
A few hours later, the RCMP said everything was OK and the company resumed normal operations around 10 a.m.
What was the threat?
One employee told CBC News there was a bomb threat, while others said they were only told to evacuate the building.
The RCMP haven't released any information on the incident.
IMP Aerospace and Defence repairs military aircraft and last week the company announced it would be laying off 44 employees.
"Based on the information that we have, we don't see any connection between that and the layoffs. This seemed like a completely unrelated incident," said Galley.
The laid off workers could be back on the job within months, according to IMP.
The company said the layoffs were due to a temporary delay, rather than an outright cancellation of a contract with the Department of Defence.
Galley said the temporary shutdown will have little impact on the company's work.