Suspect is the person police are looking for in a particular crime. They have been named, arrested, charged, or in some way, implicated.
Better would be, “ The man ( or woman or child ) the police are looking for.. “
Crimes are committed by robbers, rapists, thieves, men, women, bad guys, gunmen, thugs…etc. They are not committed by suspects.
“The robbers tied up the couple and then ransacked their home.”
There is no such thing as an UNKNOWN suspect. To look for a suspect, police must know who they are, or something about them.
“Police are talking to neighbors to see if any of them saw the suspect rapist running from the area.
“Police have no suspects”- That’s correct. Avoid “the suspect can be seen beating the store owner on surveillance video.” The video shows the ROBBER beating the store owner!