People who suffer with psychosis/schizophrenia are far more likely to be victims of violence than perpetrators.
And if they are violent the most likely person they will be violent towards is themself.
The assertion is discriminatory and offensive.
I wish the media/people in general would stop thinking every 'bad' thing was done by a 'psycho' it simply isn't true.
It's a fact that there have been random murders like this committed by people who are schizophrenic/suffering psychosis. I don't think it is offensive to suggest that might be the case here. Nobody is saying most people who suffer these conditions would do this. But some do.