The witness further explains that more lights followed after the first four lights disappeared. He saw light after light come off the sky from north and traveled the same path and speed of the four initial lights. He estimated a total of 12 more lights that were around 30 seconds apart from each other travelling at a constant speed and eventually disappeared. He further estimated that each light lasted for about 75-90 seconds before it fully vanished.
Many have speculated that the UFOs were simply Chinese Lanterns. These lanterns are usually small balloons that could fly above by heating the air inside using a fuel cell. The typical characteristic of a sky lantern is that it has light that flicker a bit but does not blink which is consistent to the description given by the witness.
However, no official explanation has been released regarding the identity of the UFOs travelling across the sky of Andover on December 19, 2013.