A fire ripped through Shuri Castle, a World Heritage site on Japan's southern island of Okinawa, early on Thursday morning, according to local authorities. 

The Naha city fire department received an emergency call reporting a fire at the castle at about 2:40 a.m. Japan time, according to public broadcaster NHK. 

The fire was put out around 1:30 p.m. local time. There is no report on casualties. 

Shuri, built more than 500 years ago, has been destroyed and rebuilt after many fires. The main hall was restored in 1992. 

An investigation into the cause of the fire is underway. Police are now looking into whether the workers were properly using electricity, reported NHK. 

The Japanese government is considering adding funds to a supplementary budget for the current fiscal year to support restoration work, according to the reports.

Chief Cabinet Secretary Yoshihide Suga said the government will do all it can to reconstruct the buildings, calling Shuri Castle an extremely important symbol of Okinawa.