ASP.Net MVC kendo File Upload validations not working

I have a simple Kendo MVC File Upload control. I want to restrict the file size and file type. Please find my code below:

<div>
    @(Html.Kendo().Upload()
        .Name("files123")
        .Async(a => a
            .Save("Save", "Upload")
            .Remove("Remove", "Upload")
            .SaveField("files")
        )
        .Validation(validation => validation.AllowedExtensions(new string[] { ".pdf" }))
    )
</div>

When I select an invalid format, it goes to the controller and the validation never gets fired.

I have spent considerable amount of time on this and could not find out any thing as nothing is happening.

Any inputs would be really helpful.

Kendo Upload validation is added after Kendo R3, 2016 release.

Here is the link: http://docs.telerik.com/kendo-ui/controls/editors/upload/validation