Chinese prosecutors have charged the wife of disgraced former official Bo Xilai and a family employee with the murder of a British businessman, a significant development in a political scandal that has embarrassed the Chinese leadership.

In a report Thursday, the official Xinhua news agency said Bo’s wife Gu Kailai and the employee Zhang Xiaojun recently were charged with “intentional homicide” in the death of Neil Heywood, who had business dealings with the couple.

Xinhua said Gu and Zhang are suspected of poisoning Heywood, who was found dead in a hotel last November. It said Gu and her son, surnamed Bo, had a disagreement with Heywood over “economic interests.” Prosecutors said Gu plotted the murder because she was worried about what they called “Heywood’s threat to her son’s personal security.”

It is the first time China has confirmed a motive for the alleged murder and the connection to the case of the couple’s son, Bo Guagua. The younger Bo recently graduated from a program at Harvard University in the United States, but his whereabouts were not immediately known.

Xinhua also confirmed that Gu and Zhang will face trial in the eastern Chinese city of Hefei, far from Beijing and Chongqing, where Heywood died.

The scandal erupted in February when a longtime Bo family aide fled to a U.S. consulate and made accusations of Gu’s involvement in the Heywood case.

Bo Xilai was a rising star in the Chinese Communist Party, serving as party chief of the city of Chongqing, until authorities removed him from the post in March as part of a massive corruption probe.

The elder Bo remains under house arrest.