You asked, "Is it right to compound this unfortunate incident by describing the suspect as yet-unidentified?"
By definition, a "suspect" is a person believed to have committed a particular crime. Someone, even if not yet identified by name, can be considered a suspect if he or she has already been described by a credible eyewitness as the perpetrator of that crime.
Now, in a news report, describing the suspect as "yet-unidentified" isn't wrong if it's clear that considerable effort over several days or weeks has already been undertaken to identify him or her. The "yet" is uncalled for and must be dropped if no formal intensive effort to identify the suspect has started because the incident has just happened, as in a bomb explosion that happened only the day before; in short, describing the suspect for a very recent crime as "unidentified" is enough.
