Saudi security forces foiled an attack near the king's palace in Jeddah on Saturday, leaving one attacker and two royal guards dead.
The palace is located next to the King Abdulaziz Road and Andalus Road on the waterfront of the city, reports Al Jazeera.
The Saudi government has not issued an official statement confirming the incident.
Groups such as al-Qaeda and more recently the Islamic State of Iraq and the Levant (ISIL, also known as ISIS) carried out a number of attacks in Saudi Arabia.
Attackers targeted Shia mosques in the country's eastern provinces where much of its Shia minority is based, as well as security forces.
In July this year, Saudi authorities said they foiled an attack on the Grand Mosque in the Muslim holy city of Mecca, which they blamed on ISIL.
Hundreds of Saudi citizens travelled to Syria to join the group.