By The Straight Times/ Asia News Network
Yam, 64, was speaking on stage as a guest at the event when a man suddenly charged towards him, according to videos of the incident circulating online.
From clips uploaded shortly after the incident, the man can be seen taking a weapon out of his pocket before aiming it towards Yam.
He then lashes out at Yam repeatedly as the actor frantically tries to move away while clutching his abdomen.
Many people in the audience can also be heard reacting in shock.
A photo shared online shows the attacker being subdued by security officers.
According to the Sina Entertainment portal, a spokesman for the actor said that he remained conscious after the incident. He was taken to hospital and his wound has also been treated.