31. The lethal gas in the U . S ., although five states still permit its use in varying circumstances. 32. As soon as the crystals were exposed to the air, they turned into a lethal gas that killed within minutes. 33. The first person to be executed in the United States by lethal gas was Gee Jon, on February 8, 1924. 34. The lethal gas is believed to have been hydrogen cyanide, Mears said, but further testing is needed to confirm that. 35. He was sprayed with lethal gas after stepping out of his home, the report said, but apparently didn't realize it. 36. David Mason however chose to die from lethal gas in August 1993, just seven months after lethal injection was introduced. 37. Wiese said police had also found chemicals on the property that could be used to make a second lethal gas . 38. This remained the law until March 28, 1921 when an amendment was adopted providing for execution by means of lethal gas . 39. Saddam's forces attacked them in 1988, killing an estimated 5, 000 Kurds when his helicopters dropped lethal gas on one town. 40. Arizona prisoners sentenced to death for crimes committed before November 1992 have the option of choosing between lethal injection or lethal gas .
