I received this in an email and  posting it hoping that by doing so it may prevent accidents involving  the drilling line in the future.The accompanying photos are of a tragic accident and are not suitable for all viewers.
Warning-This Article contains some very graphic photos of  Deceased accident victims still on the Rig Floor. 
The paragraph that follows accompanied the email; 
"At The Pemex Monthly Safety Review with Sub-Contractors we spent a considerable amount of time listening to the causes & current status of the investigation into the accident on the Sonora Drill Line Failure.Here is a brief summary of the notes I took; The rig had completed drilling and they were RIH with 7 5/8" production ,tie-back string at 4772mts./15656ft. The tie-back string/elevators were 1.5 mts/4.9ft above the rotary table. String weight was 264k. At 18.50 hrs. a loud noise was heard. The traveling assembly fell a short distance and got caught/trapped in the stands of pipe that were racked back in the derrick. The drill string parted in four (4) different locations & dropped to the rig floor. The falling drill line was the primary cause of the deaths & injuries. The rig floor was littered with +/- 4" long sections of drilling line. (H2S embrittlement?/or harmonics?/or incorrect materials used in the manufacturing process? The accident happened during meal time, and only eight persons were on the rig floor at the time of the accident. Normally, during this phase of the well, there would have been as many as 15 persons around the rig floor i.e. ( Driller ,AD, Derrickman, 3 floormen,3 casing running crew, 1 pipe thread inspector, 2 or 3 completion techs, Co. Rep. or Completion Engineer etc.) One Assistant Driller & two Floormen were killed & the casing running crew sustained small to severe injuries. The persons who were killed or injured were all around the V-Door area. One person who was standing in front of the Drawworks was untouched by the falling drilling line. The rig was audited on the 1st of March, without any non-compliance items noted. The investigation team has verified that the drill line, slip & cut procedure on this rig was being followed correctly. The drill line was slipped & cut on the 14th of April & slipped on the 23rd of April. Items pending verification are Crown & traveling assembly sheaves are to be examined for wear & undergo a non destructive test. The drill line will be pull tested & subject to a material analysis. The drill line was manufactured in Mexico by a Mexican company called Camera (this name could be misspelled). The sheave guard inspection is ongoing. The review of the records and the planned periodic inspections is ongoing."
See The Photos >>>