Background: Aggression and suicidality prior to the initiation of treatment are frequent phenomena in psychosis patients. Increased scores in the Brief Psychiatric Rating Scale Excited Component (BPRS-EC) have been shown to predict involuntary treatment, aggression, and suicide in first-episode psychosis (FEP) patients. However, it is unclear if an agitated-aggressive syndrome as measured with the BPRS-EC is already present in at-risk mental state (ARMS). Methods: BPRS-EC scores from 43 ARMS patients, 50 FEP patients, and 25 healthy controls (HC) were analyzed. Multivariate analyses were performed to review if group differences were mediated by potential confounders. In addition, the association of BPRS-EC scores with clinical variables was examined. Results: BPRS-EC scores were significantly different across diagnostic groups (H(2). = 22.1; p<. .001), and post-hoc analyses showed significantly higher BPRS-EC scores for ARMS (p= .001) and for FEP patients (p<. .001) compared to HC. Differences remained significant after controlling for gender, years of education, and intelligence. No significant differences emerged between ARMS and FEP patients. BPRS-EC was significantly correlated with lower intelligence (r= - .27; p= .008), reduced level of functioning (r= - .44; p<. .001), and with smoking behavior (r= .22; p= . .019). Conclusions: ARMS and FEP patients in our sample had significantly higher BPRS-EC scores compared to HC. This may constitute a correlate of an agitated-aggressive syndrome and an increased risk for aggression and suicidality.