Legal experts have called for China to clarify rules that require courts to inform the relatives and lawyers of death-row prisoners ahead of an execution.

The call comes after Zeng Shan, in central Hunan province, said she was not told ahead of time about her father's execution.

Zeng complained on Sina Weibo, China's version of Twitter, on Friday about the Changsha Intermediate People's Court's handling of the case, setting off controversy.