Aviation experts are expected to complete late Friday their investigation into an unidentified flying object that disrupted air traffic over east China for an hour on Wednesday.

An investigation team, comprising police and aviation officials, are still trying to identify the UFO that was located over Zhejiang Province.

"No conclusion has yet been drawn," said Wang Jian, head of air traffic control with Zhejiang branch of the Civil Aviation Administration of China, told Xinhua Friday.

Media have reported speculation that the UFO might have been a private aircraft, based on the increasing number of privately-owned aircraft in the province.

But an industry insider who declined to be named Friday ruled out the speculation as "too unprofessional" without giving further explanation.

Wang Jian said the private plane was "just a guess."

Xiaoshan Airport in the provincial capital of Hangzhou was closed after a UFO was detected at around 9 p.m. Wednesday, and some flights were rerouted to airports in Ningbo and Wuxi cities.