I got the impression that Benali wants to get rid of the time stamps completely and merge the content into a single paragraph. When I copy/pasted from the original post, the lines were separated by a soft return rather than a paragraph mark so I'm going to assume that is what the code needs to work with.
If the above assumptions are right, building on from Paul's code try...
Code:
Sub Demo()
Application.ScreenUpdating = False
With ActiveDocument.Range
With .Find
.ClearFormatting
.Replacement.ClearFormatting
.Text = "([0-9:]{5})"
.Replacement.Text = " "
.Forward = True
.Format = False
.Wrap = wdFindContinue
.MatchWildcards = True
.Execute Replace:=wdReplaceAll
.Text = "^l" 'or ^13
.Replacement.Text = ""
.Execute Replace:=wdReplaceAll
End With
End With
Application.ScreenUpdating = True
End Sub