Bogus Gun Calls?

This may just be a coincidence, or I may be totally wrong, but it seems that someone is calling in bogus "man with a gun" calls.  Yesterday afternoon there was a report of a man that had pointed a handgun at a transient in the shopping center at Blacow and Grimmer.  A detailed description of the suspect and woman with him were given as well as their location.  Officers arrived and detained the two subjects, but to the best of my knowledge, neither the victim or reporting party could be located.  I don't believe a gun was found as I don't recall one being run for wants.
Last night a man called in a disturbance near the Honda dealership down at Pacific Commons.  About 6 men were in a loud argument around the corner from the dealership and one subject had a handgun.  He did not brandish it in a threatening way, the man indicated, but merely was holding it in his hand.  Officers formed up and rolled in making felony stops on all subjects, having them prone out in the street and later cuffed.  I don't think a gun was found here as well.  The reporting party said he was a Honda employee and gave his name and cell phone number which seemed to match, but could not be located.  But the manager at Honda said those that were detained are his employees and the name given by the caller is not an employee. 
Of course this is a dangerous situation for officers to roll in on and I hope my analysis is wrong.