Repeater not firing ItemCommand event in Kentico CMS in ASP.Net

I have checked this code and its working fine here. I have bounded the Repeater in not in postback and i am able to detect the RepeaterItemCommand while debuggin.

Page

<%@ Register Src="~/UserControls/RepeaterControl.ascx" TagName="RepeaterControl"
    TagPrefix="uc" %>
<form id="form1" runat="server">
    <div>
        <uc:RepeaterControl runat="server" />
    </div>
</form>

UserControl : working without using UpdatePanel also

<asp:UpdatePanel runat="server">
    <ContentTemplate>
        <asp:Repeater ID="rptImages" runat="server" OnItemCommand="rptImages_ItemCommand">
            <ItemTemplate>
                <asp:ImageButton ID="Imgbtn" runat="server" Style='height: 80px; width: 80px' ImageUrl='<%# Eval("ImageUrl") %>' />
            </ItemTemplate>
        </asp:Repeater>
    </ContentTemplate>
</asp:UpdatePanel>

UserControl.cs

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        DataTable dt = new DataTable();
        dt.Columns.AddRange(new DataColumn[1] { new DataColumn("ImageUrl", typeof(string)) });
        dt.Rows.Add("../Images/Chrysanthemum.jpg");
        dt.Rows.Add("../Images/Penguins.jpg");
        dt.Rows.Add("../Images/Desert.jpg");
        dt.Rows.Add("../Images/Hydrangeas.jpg");
        dt.Rows.Add("../Images/Garden.jpg");
        this.rptImages.DataSource = dt;
        this.rptImages.DataBind();
    }
}
protected void rptImages_ItemCommand(Object Sender, RepeaterCommandEventArgs e)
{
    string ImageURL = ((ImageButton)e.CommandSource).ImageUrl;
    if (ImageURL.Contains("Store"))
    {
        // Response.Redirect(Constants.stored);
    }
    if (ImageURL.Contains("Credit"))
    {

        //Response.Redirect(Constants.Credit);
    }
}

 I dont know about Kentico CMS. but the code above is working.