I was in the the hotel el peten in flores sitting at the balcony and watching birds just before coming heavy rain and thunder storm. my wife first noticed the object coming across the lake (in front of the hotel) around 500 metres over ground. it was no plane, no helicopter, no baloon or comparable.It was a green disc situated in the air with a 45° angle, flying abruptedly forward, standing, flying again. i took my camera mounted a lens with 300mm focal length and began to shot pictures. the object crosses the lake and vanished abruptly in the north. because i had seen and taken pictures of several ufos in my life i was not extremely surprised but happy to see one again.