It feels like police are keeping things unusually tight lipped for a reason. Typically you hear police make a statement that allay public concerns, (eg we don’t believe this was a random act or public isnt in danger, may have been an accident etc) or, conversely, police warn the public to be careful (lock your doors, travel with a buddy etc.). It seems here that they are purposefully keeping whatever they know/suspect a secret (I’d guess so their suspect doesn’t know for sure they are on to him/her—particularly if the suspect is engaged in ongoing conversations with police (eg someone who knows Heidi and is offering info about her). Once someone knows they are a suspect, they will likely zip it.