Some Chinese media claim that witnesses saw the police take one woman away that was sprinkling herself in petrol, in what appeared an attempt to self-immolation. If this second episode is confirmed, it would support a coordinated attack between at least two people.
Dozens of demonstrations take place every week in China, but reporting is suppressed. Two incidents in one day, in the huge capital city could be coincidence.
The tactics are very different in the two cases. Self immolation is the trademark of the Chinese religious group Falun Dafa (Falun Gong). They have no grievance against the US.