When I was working as a young receptionist for an international oil company, I answered the switchboard to a man calling for my flatmate (who worked for the same company). I transferred it through to her without giving it a second thought.
A minute or so later I answered another call and spoke to a gentleman who was doing a poor impersonation of Peter Sellers as Inspector Clouseau. He asked for me. When I acknowledged myself he said, once again using the awful accent, that there was a “bermb in the building”. He then promptly hung up.
Even though I was quite young it did occur to me that this was a hoax, but then my flatmate called the switchboard and we swapped stories about our calls from the same man. However it was the 1980s, during the time of the Iran-Iraq war and working in a large oil company came with some responsibilities.
From there the panic button was hit. The big-wigs were informed and she and I were questioned under close scrutiny. The police were even called in and we were questioned further. However, because we were flatmates and friends it was the general consensus that it was a practical joke being played upon us, but we had no idea by whom.
One of the young police constables took a fancy to me and we ended up dating for many months, but our relationship just lacked spark, and I think our number was up after a night at the movies to see Mad Max. The movie was interrupted halfway through when the cinema was evacuated due to a … a bomb threat.