Feng said the theft shows that some security facilities inside the museum might "have some problems," adding that the museum will adopt new security equipment and tighten relevant measures.

Feng said the museum has ordered all of its departments to thoroughly search all stockhouses, exhibition halls and security facilities for the missing items, as well as clues to their whereabouts.

Feng also claimed that the photos circulating on the Internet about the theft were not genuine.

At the same news conference, Wang Xiahong, representative of the Liang Yi Museum, expressed "absolute trust" in the Palace Museum, and said the museum will continue its visiting exhibition in the Beijing-based museum as planned.

She was "shocked" when she was informed of the theft on Monday morning, Wang said, but "the incident was not foreseeable. It already happened, and I hope that the Palace Museum doesn't feel too guilty about it."

Wang didn't reveal the market values of the stolen items, saying that the market values cannot reflect the historical significance the art pieces bear.

Feng said that the Palace Museum will restore and arrange the temporary exhibition as soon as possible, and ensure the safety of the remaining pieces.

The exhibit is temporarily closed but expected to reopen soon.

Feng said that the incident has been reported to the State Administration of Cultural Heritage and the Ministry of Culture.

The Palace Museum last encountered a case of theft in 1991. That case was eventually solved.