A.LeClair said:
From the various witness accounts (not to mention the 2 videos) that have surfaced on various internet forums, it is fairly clear that this sighting involved "fire balloons" ("Thai lanterns").
The description of the orange lights travelling across the sky together without making any sound is a fairly classic description of prank fire balloons (or balloons with lights attached).
Prank "UFO" fire balloons have traditionally been made by using transparent, lightweight plastic laundry bags with birthday candles propped at its base by drinking straws, wires or balsa wood structs. When the candles are lit, the hot air makes the bag rise. Now, more sophisticated fire balloons / thai lanterns can now be purchased from commercial suppliers, such as the ones below, for use at weddings and other celebrations:
http://www.weddinglanterns.co.uk/
http://www.ribbands.co.uk/prdpages/lantern.htm
These balloons/lanterns have become increasingly popular in the UK in the last few years. See, for example, the news report (in relation to a previous "UFO" incident) on the BBC website at the link below:
BBC NEWS | UK | England | Essex | Wedding lanterns spark UFO scare
The duration for the current sighting (said to be about 10 minutes) is consistent with this explanation. Ufologist Allan Hendry (author of the very informative book "The UFO Handbook") refers to 14 reports of UFO caused by prank fire balloons, stating that those 14 sightings had durations of perceived flight from one to 15 minutes.
Fire balloons have been discussed by the authors of several UFO books and several skeptical books.
They are also discussed in some detail in the Condon Report.
See, for example, the discussions of Case 45 at pages 605-606 (in Section 4, "Case Studies", Chapter 2) and pages 458-465 (in Section 4, Case Studies, Case 18) of the version of the Condon Report available online at the links below:
http://ncas.sawco.com/condon/text/contents.htm
SHG - Condon Report: Table of Contents
Please note: Since they are a fire hazard, I understand that such products are illegal in several states in the USA.
Kind Regards,
Isaac Koi