If even parts are true, it would be very disturbing. The PRC is surely doing their investigation. But so are western (including US) intelligence agencies. Possible scenarios include: 1. Accidental release 2. Deliberate release by a lone wolf, disgruntled lab employee (e.g. Insider Threat), think Dr Bruce Ivins, anthrax 2001. Very scary. 3. Deliberate release by an employee manipulated by a foreign rogue agent or group. Example: Aum Shinrikyo 1995 Sarin release in Tokyo. 4. Deliberate state-sponsored release. Very unlikely and suicidal, to be frank. Nobody gains, everybody loses. And states, even authoritarian ones, are rational actors.

None of the above hypotheses (some of which are now in the mainstream media) are good. And the public may never know the truth. Any findings are likely to be classified.