An explosion ripped a remote area of the Mojave, Calif., installation of Scaled Composites, the firm that built the pioneering Space Ship One, according to wire reports.

The blast last week, causing injuries and deaths, apparently occurred during use of nitrous oxide.

Space Ship One ventured more than 60 miles up in a suborbital flight, becoming the first private manned vehicle to achieve space flight, and then made two other flights.