Updated

A Chinese state media report says security for the upcoming Shanghai Masters is being tightened after an online death threat against Roger Federer.

Shanghai's Youth Daily quoted tournament official Yang Yibin as saying police were notified about the threat and that security will be increased for Federer at the tournament, which starts this weekend.

An officer in the Internet security office of the Shanghai police said Friday that the threat is being investigated. In a statement, the tournament said it is aware of the threat and has proper security in place.

The report says the threat, posted last month on a Federer fan site by "Blue Cat Polytheism Founder 07," vowed to assassinate Federer. It was accompanied by a gruesome image of a decapitated Federer.