Repeater causes postback of the whole page even if it's inside an update panel - asp.net

Question

I have an user control that contains an update panel with a repeater. The repeater has a button used to delete records.
The problem is when I press the delete button, and a record from the repeater gets deleted, a postback on the whole page is triggered. From my understanding, only the section inside the update panel should refresh.
I should also mention that on my master page I have a script manager with the property "EnablePartialRendering" set to true.
Can someone help me with this problem? Thanks in advance.
ASP file:
<%# Control Language="C#" AutoEventWireup="true" CodeBehind="ActivityFiles.ascx.cs" Inherits="Training.User_Controls.ActivityFiles" %>
<asp:Repeater ID="FilesRepeater" runat="server">
<HeaderTemplate>
<table class="table table-bordered">
<tr>
<td><b>Name</b></td>
<td><b>Description</b></td>
<td><b>Actions</b></td>
</tr>
</HeaderTemplate>
<ItemTemplate>
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<tr>
<td><%# Eval("Name")%></td>
<td><%# Eval("Description")%></td>
<td>
<asp:LinkButton ID="DownloadFile" runat="server" OnClick="DownloadFile_Click" Font-Size="Large"
file-path='<%# Eval("Url")%>'>
<span class="glyphicon glyphicon-floppy-disk text-info" aria-hidden="true"></span>
</asp:LinkButton>
<asp:LinkButton ID="DeleteFile" runat="server" OnClick="DeleteFile_Click" Font-Size="Large"
file-id='<%# Eval("Id") %>'
file-path='<%# Eval("Url") %>'>
<span class="glyphicon glyphicon-trash text-danger" aria-hidden="true"></span>
</asp:LinkButton>
</td>
</tr>
</ContentTemplate>
</asp:UpdatePanel>
</ItemTemplate>
<FooterTemplate>
</table>
</FooterTemplate>
</asp:Repeater>
.cs File:
protected void Page_Load(object sender, EventArgs e)
{
activityId = (int)Context.Items["activityId"];
if ( ! IsPostBack && Visible)
{
if (activityId != 0)
{
LoadFiles();
}
}
}
private void LoadFiles()
{
DataTable files = DatabaseHelper.SelectAsDatatable(FilesQueries.GET_ACTIVITY_FILES, new Dictionary<string, object> {
{ "activityId", activityId }
});
FilesRepeater.DataSource = files;
FilesRepeater.DataBind();
if (files.Rows.Count == 0)
{
FilesRepeater.Visible = false;
NoRecords.Visible = true;
}
}
protected void DeleteFile_Click(object sender, EventArgs e)
{
// TODO: modify this function to work only with the fild id
LinkButton deleteButton = (LinkButton)sender;
string fileId = deleteButton.Attributes["file-id"];
string filePath = deleteButton.Attributes["file-path"];
DatabaseHelper.ExecuteNonQuery(FilesQueries.DELETE_FILE, new Dictionary<string, Object>() {
{ "#fileId",fileId },
});
//delete file from disk
string path = Server.MapPath(filePath);
FileInfo file = new FileInfo(path);
if (file.Exists)
{
file.Delete();
}
LoadFiles();
}

Answer 1

Found the solution on another stackoverflow post (See Eugene S answer)
You have to manually add you control to Script Manager. You should do that inside File Repeater's Item created event. Good luck.