A gardener at a zoo in Shenzhen died from wounds inflicted by five tigers after he climbed over the glass barrier of a bridge and fell into their pen. Sheng Jinhua , 54, was seen in the pen containing nine South China tigers at around 2.45pm on Thursday at Shenzhen Safari Park, the Guangzhou Daily reported. His colleagues, seeing five tigers starting to maul him, drove a vehicle into the enclosure to intervene, but it was too late. Sheng died of severe bite wounds. The tigers involved were quarantined. A witness said the gardener had climbed onto the bridge, which is built on stilts over the pen. The sides of the bridge are protected by glass 1.8 metres tall. 'Four or five tigers had gathered and looked up to see Sheng as he was climbing over the glass barrier,' the newspaper quoted an animal feeder as saying. The feeder said he had no idea what Sheng was trying to do when he fell into the pen. The feeder quickly found and ignited a line of firecrackers to drive the tigers away, but that tactic failed. He found a vehicle to drive into the enclosure, but when he arrived, Sheng was already dead. Zoo officials said Sheng had violated safety rules when he climbed over the glass barrier. Xinhua added that police were investigating. According to the zoo, gardeners were supposed to be off work at 2pm, but Sheng returned without notifying anyone. There are flower pots on the bridge, but officials said a gardener would have no reason to climb over the barrier.