Firemen inspect the damage after a fire at the 17th century Hotel Lambert in the Ile Saint Louis in Paris, Wednesday. The palace, listed as a national monument, was purchased in 2007 by a member of the Qatar's royal family and currently in restoration. — Reuters PARIS — Some 140 firefighters spent six hours Wednesday morning fighting a major blaze at a 17th-century mansion in Paris owned by a Qatari prince. Firefighters rushed to the Lambert Hotel in central Paris, a private mansion that was bought in 2007 by Prince Abdullah Bin Abdullah Al-Thani, an uncle of Qatar's new emir, at around 1.30 a.m. Wednesday. Having successfully fought the blaze, fire crews later inspected the damage to the building. The Qatari bought the mansion from the Rothschild banking family for some $85 million, in an acquisition that sparked dispute as heritage activists feared he would destroy a cultural gem. A French court initially blocked Prince Abdullah's plan to modernize the mansion, including installing a vehicle lift. The dispute was finally resolved in January 2010 when the prince signed an agreement with the heritage association Historic Paris after weeks of delicate government-supervised negotiations. Under the agreement, the association withdrew legal proceedings against the prince, described by the ministry as “a great friend of France” who cares for its heritage. The mansion is considered one of the finest examples of mid-17th-century French architecture, featuring frescoes by Charles Le Brun and other masters of the day, and is part of a World Heritage site along the banks of the river Seine. The fire, which broke out overnight on the roof of the building, “spread pretty fast because the building is empty and in the midst of renovation”, fire service Lt. Col. Pascal Le Testu said. “The operation was complicated because the structure is fragile,” he said. “Now we have to see how badly the structures were affected as well as the state of the artworks inside that may have been reached by smoke and flames, but also water, despite our utmost efforts to protect them,” he added. Built in the 1640s at the eastern tip of the Ile Saint-Louis, the mansion was designed for a wealthy financier, Nicolas Lambert, by the architect Louis Vau, who went on to oversee an expansion of the Chateau de Versailles for Louis XIV. Rich with history, the mansion's uses over the years have included being a hideaway for the 18th-century philosopher Voltaire and his lover, and a political headquarters for Polish exiles in the following century. — Agencies