GlaxoSmithKline Plc is investigating a complaint about how employees in China sell the Botox wrinkle treatment to doctors, adding to the U.K.’s drugmaker woes in the country as Chinese police probe allegations of corruption.

The same whistle-blower who made previous accusations about corruption at Glaxo in China apparently is behind the Botox complaint, Simon Steel, a company spokesman in London, said in an e-mail today. The whistle-blower says salespeople gave doctors cash and perks for prescribing the product, the Wall Street Journal reported today, citing internal documents and e- mails it reviewed.

“We are investigating these new claims,” Steel wrote. “However, our inquiries to date have found no evidence of bribery or corruption in relation to our sales and marketing of therapeutic Botox in China.”

Senior executives at Glaxo China are suspected of “economic crimes” and are being investigated by Changsha public security officials, the city’s police force said June 28 on its official blog, without elaborating. A senior Glaxo finance executive in Shanghai and employees in Beijing were detained as part of a corruption investigation, the South China Morning Post said July 1, citing an unidentified person from Shanghai’s drug industry. Glaxo will cooperate with the investigation, Steel said July 1.

E-mails and documents discuss a marketing strategy for Botox that targeted 48 doctors and planned to reward them with cash or educational credits, based on the number of prescriptions made, the Journal reported today. The strategy was called “Vasily,” borrowing its name from Vasily Zaytsev, a noted Russian sniper during World War II, the report said, citing a 2013 PowerPoint presentation.

“We have investigated the specific claim on the so-called Vasily program,” Steel wrote. “Our investigation has found that while the proposal didn’t contain anything untoward, the program was never implemented.”

A four-month investigation of the same tipster’s previous allegations turned up no evidence of wrongdoing, the company said June 13. The whistle-blower alleged Glaxo’s sales staff in China bribed doctors to prescribe medication, in some cases for unauthorized uses, between 2004 and 2010, the Wall Street Journal reported last month.

Glaxo licenses from Allergan Inc. the right to sell Botox in China and Japan.