A prominent Chinese government forensic scientist has questioned the cause of death of a murdered British businessman, casting doubt on the official version of a scandal that reached into the upper levels of the Communist Party.

In a post to her blog that has since been removed, Wang Xuemei, a forensic expert with the top prosecutors' agency, said the official accounts lack sufficient evidence that Neil Heywood died from cyanide poisoning, which she describes as leaving the body obviously discolored.

Heywood's murder in November is a central element of the scandal which led to senior Chinese politician Bo Xilai's ouster from the leadership. Bo's wife, Gu Kailai, was given a suspended death sentence last month after confessing to murdering Heywood over a business dispute by pouring cyanide into his mouth.

Wang confirmed in a phone interview Thursday that she is the author of the blog entry posted late Wednesday detailing her suspicions about the case. She said she has had no access to the evidence, but points out discrepancies in details that have been made public.

Wang said acute cyanide poisoning usually causes a quick death with noticeable symptoms such as convulsions, coma and a sudden halt in breathing that Gu or Gu's accessory should have described in their account of the crime, but did not.

Despite the absence of such testimony, "our court went as far as to accept the conclusion of cyanide poisoning as the cause of death. About this, I feel very pained, very uneasy, very frightened!" Wang wrote.

Prosecutors who handled Gu's case either declined comment or could not be reached. Wang's posting marks the first time a senior law enforcement figure has questioned the government's public version of the messy scandal.

In the official account, Gu's murder of Heywood in a hotel in the city of Chongqing was initially covered up by Bo's longtime aide, police chief Wang Lijun. After becoming estranged from Gu, and later Bo, Wang fled to the U.S. Consulate in nearby Chengdu, fearing for his life. Wang was sentenced to 15 years in jail on Monday for his thwarted defection bid and for helping to cover up the murder.

Beyond that pre-packaged version, the scandal exposed divisive infighting in the party and distracted leaders from preparing for a once-a-decade political transition.

Wang, the forensic expert, wrote that the local forensic specialists who handled Heywood's body before it was cremated would have immediately observed the discoloration of the corpse or that blood samples were abnormally bright red in color, yet none in such a position have been held accountable for apparently assisting in the cover-up.

Wang said she did not doubt that Gu intended to murder Heywood and tried to carry it out. However, she said the poison was likely not enough to kill Heywood and that someone else's involvement in finishing Heywood off could not be ruled out.