A man stabbed three performers during a live show in Saudi Arabia's capital, state television reported on Monday, adding that the victims were in stable condition.
In scenes that were unimaginable just two years ago, Saudi Arabia has staged glitzy performances by a host of international artists, from South Korean boy band BTS to pop icon Janet Jackson and rapper 50 Cent.
But Saudi officials warn that introducing such reforms in a society steeped in conservatism is fraught with risk.
While they are wildly popular among Saudi Arabia's majority young population, the reforms could anger arch-conservatives, including hardline clerics and the religious police whose powers have been clipped in recent years.
"Liberals and conservatives in the kingdom are on a collision course and that probably worries Saudi leaders the most," Quentin de Pimodan, a Saudi expert at the Greece-based Research Institute for European and American Studies, told AFP.
"After this attack we can expect a sharper crackdown on those opposed to Saudi's entertainment push."
The motive for the attack was not immediately clear. Saudi Arabia intervened in Yemen's civil war in 2015 against the Iran-aligned Houthis.
SPA said the victims, two men and a woman, sustained "superficial wounds" and were stabilised after receiving medical care.
The General Entertainment Authority has said it plans to pump $64bn into the sector in the coming decade.