A major police hunt for a man supposedly seen roaming around Blackpool with a firearm was sparked by a boy with a toy gun, the force said.
Civil servants in offices off Warbreck Hill Road, Warbreck, were kept in lock-down at around 5pm on Monday night as armed officers stood guard outside - and as the force helicopter scoured the area.
Lime Grove was closed as a manhunt was launched without success, with the operation finally stood down four hours later with no arrests being made.
Now, following a "number of extensive enquiries", Lancashire Police said it had "established this was the case of a boy carrying a toy gun" and that "no real weapons were present".
One civil servant, who did not want to be named, said they were told on Monday to stay inside because "there was a man outside with a gun on the playing field by the Rock Gardens".
Staff were kept inside for around an hour before being allowed home, it was understood.
Police said the 999 call was "made in good faith", with officers' response "based on the information we had at the time".
DCI Lee Wilson, from Blackpool CID, said: "I understand that the response to this incident may have concerned local residents but we have to take all reports seriously.
“Each time a firearms incident is reported to the police we have to respond in a controlled and proportionate way.
"We have a large number of incidents reported that turn out to be imitation or even toy guns, however, we also have those that are genuine.
“The report was made in good faith and we would always encourage people to have the confidence to report any suspicious activity to us.”
Yesterday, police said they had upped patrols in the area in a bid to reassure residents and workers.