No news could mean anything - perhaps they have a good idea that they're in an area but don't want to spook them by saying they've been spotted in X area. Perhaps they've no new leads at all.
The police normally put out something when a missing person they've been looking for is found - "The missing person we were looking for, Fred Smith, has been located safe and well" or "officers looking for Fred Smith have found a body. Formal identification hasn't taken place yet, but his family has been informed".
Sometimes no news is just no news.