Angular 8 – code after navigating from within interceptor

What happens if I navigate from within an interceptor? See my code below. Will it neglect all other code that should have come after routing, or will it continue to execute the code? Will it reach throwError and will it reach the service doing the HTTP request and the component calling the service request method in case of error 500 (also what happens at 401)?

    intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
    return next.handle(request).pipe(
        catchError(err => {

            let errorMessage = '';
            if(err instanceof HttpErrorResponse) { // server side error

                switch (err.status) { 
                    case 401:
                        errorMessage = "Ongeldige inloggegevens"  
                    case 500:     //server error
                        let error = "Er is iets mis gegaan! Probeer het later nog eens.";
                        this.router.navigate(['error500'], { state: { message: error, title: 'Error ' + err.status }});

            return throwError(errorMessage);

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Source Url Angular 8 – code after navigating from within interceptor