Actor Russell Crowe believes he has caught a UFO on film flying over Sydney's Botanical Gardens.

" The usually publicity-shy Gladiator performer said he captured what appears to be several flying objects whizzing over Sydney's Botanical Gardens earlier this week and he's posted the results on YouTube. "

Crowe had borrowed the camera in order to film some bats over the gardens but instead discovered he had caught a strange glowing red object flying overhead. He later posted the time-lapse video on Youtube prompting significant interest from web users. "A friend and I set camera to capture fruit bats rising from Botanic Gardens. This was a big surprise," he wrote on Twitter.It isn't clear exactly what it is that the actor caught on the footage. Some have suggested that the glowing red anomaly is the result of lens flare however Crowe dismissed this idea. "Canon 5D, no flash, can't be lense (sic) flare because it moves, camera is fixed," he argued. "The camera is on a balcony - not behind glass."