At least two cops need to get sent for all robbery alarms or robberies that are still happening. If they can, the call taker needs to try and get the caller the stay on the phone so that they can keep giving updates. The cops that get sent on robbery calls always need to be extremely careful in these kind of situations.
The cops should check the situation out to find out if they need backup to control the situation. If the first cops that get there can’t find out if the robbery is still happening, they should hide themselves in a place that gives them sight of the whole area and try to wait until others get there.
If the caller isn’t on the phone with the call taker anymore, the call taker should call back to see if the suspects are still there, this needs to be done very carefully though, so the victim doesn’t get put in more danger than they already are.