JEFOK

They come from constellation Indus.

They are known by other races as "peace-makers".

They are very advanced technologically.

Their first sighting on Earth dates back to 1500 BC.

They met with JFK 3 weeks before he was killed.

They have also (around the same time) met with other Human world leaders.

They have not been seen on Earth since JFK's death.

In 1965 they gave a message to the Human leaders that ran countries with nuclear capability (content unknown).