Q: Think it was an accident? http://newspapertree.com/news/2861
A: If they were over narco traficante airspace and were spotted, well, bad news for them. Mexico is rapidly becoming a failed state so who knows? The wreckage, if it can be examined, should tell tales that dead men cannot. People have been killing each other over water rights in New Mexico and Texas for 500 years so these guys were not just unimportant bureaucrats either. Some accidents are convenient enough that it makes you wonder. Motive-opportunity-method.