WebBrowser1.Navigate loop request - vb.net

Question

How can i make this code to loop urls continuously in Webbrowser1, after run trough these links one time.
This is the code i have so far, but when i run this, the Webbrowser stop with last url, wich is google.com. What i want to do is when the last url is reached i want it to start from top again, and run trough links again and again, until i exit the program.
Public Class Form1
Private WithEvents backgroundWorker1 As System.ComponentModel.BackgroundWorker
Dim l As New List(Of String)
Dim flagDC As Boolean = False
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Button1.Hide()
Button3.Show()
l = New List(Of String)
l.Add("http://bbc.com/sipeu/php/zq.php")
l.Add("http://google.com")
l.Add("http://DCWC.com/sipeu/us.php")
l.Add("http://google.com")
l.Add("http://example.com/sipeu/v.php")
l.Add("http://google.com")
backgroundWorker1 = New System.ComponentModel.BackgroundWorker
backgroundWorker1.RunWorkerAsync()
End Sub
Private Sub BackgroundWorker2_DoWork(ByVal sender As System.Object,
ByVal e As System.ComponentModel.DoWorkEventArgs) _
Handles backgroundWorker1.DoWork
For Each www In l
flagDC = False
WebBrowser1.Navigate(www)
Do
Loop While Not flagDC
Next
End Sub
Private Sub WebBrowser1_DocumentCompleted(ByVal sender As System.Object,
ByVal e As System.Windows.Forms.WebBrowserDocumentCompletedEventArgs) _
Handles WebBrowser1.DocumentCompleted
System.Threading.Thread.Sleep(1000)
flagDC = True
End Sub
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Button3.Hide()
ChangeUserAgent("troll001_v2-agent34")
WebBrowser1.Navigate("http://example.com/welcome.php")
End Sub
Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
Close()
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs)
End Sub