Murder by UFO

Charlie Sands was investigating UFO sightings in Austin, Texas, when he got reports of multiple sightings in a small area of the Caribbean.
He went to Isla Tintada, the apparent center of activity. It was a typical Caribbean island, settled by wealthy people who wanted to get away from their problems in other places.
He was watching as a storm approached from seaward of his position. It was colorful and beautiful, at twilight. He took two pictures of what he assumed to be the basis of the reports. He debunked them quickly, but discovered something else in those two pictures.
And ended up dead.
"Dr. John" Matthews intended to find out how and why he died.