Chief U.N. investigator Daniel Bellemare arrived in Saudi Arabia on an unannounced visit, As Safir daily reported Monday.
It said Bellemare arrived in Jeddah on Sunday night, two days after a member of the team investigating ex-Premier Rafik Hariri's assassination, Sameh Hafnawi, traveled to the kingdom.

Bellemare returned from Paris to Beirut last Thursday.

Last year, media reports said that a team of investigators collected water and soil samples from Saudi Arabia's Zalim area.

They said at the time that the team, made of Saudi specialists as well as German, Canadian and Egyptian geological experts, will take samples from three other regions in the country.

The commission has said that DNA tests of body parts in the Hariri blast scene revealed that the suicide truck bomber did not spend his youth in Lebanon and arrived in the country two or three months before his death.

Meanwhile, al-Mustaqbal daily reported Monday that the preparations, including alterations, to the building housing the international tribunal that will try Hariri's suspected assassins will be over in less than two months. 
The tribunal will be based in the Dutch intelligence service's former headquarters near the Hague.

The Hague bills itself as the legal capital of the world and is already host to several international tribunals like the International Court of Justice, the International Criminal Tribunal for the Former Yugoslavia and the International Criminal Court.