Coast Guard investigators working to determine what caused the destruction of the 37-foot sailboat off the Mexican coast, consider that there's a possibility that no eyewitnesses remain. All four crew members of the Aegean were killed. And based on the level of destruction — small pieces of the boat were found spread over a wide area — it may be no one aboard the much larger ship that's believed to have rammed the Aegean ever realized it, says the Los Angeles Times news report. Without discounting the likelihood of a collision, the Coast Guard noted that the last known position of the Aegean was close to a rocky shoreline on one of the Coronado Islands.