Tragedy struck a Midland, Tex., parade on Thursday evening when least four people were killed in a train accident. Around 5pm, a Union Pacific train hit a flatbed trailer carrying 24 veterans and their families. The group was on their way to the “Hunt for Heroes” parade to honor veterans. Another 17 were injured, and 10 of those casualties were in critical condition. What caused the accident remains unclear, but a witness said the truck appeared to have gotten stuck on the tracks. The National Transportation Safety Board says it is investigating the crash.