The death toll from an ammonia leak at the Stirol chemical plant in Ukraine rose to six on Thursday, UPI cited officials as saying. A sixth person died at the Gorlovka municipal hospital due to ammonia poisoning after the leak at the plant on Tuesday, ITAR-Tass reported. The five others who died were buried in Gorlovka on Thursday, officials said. Twenty-six people sought medical attention after the accident. The Stirol chemical plant is the largest producer of chemicals in Ukraine. Local authorities said air and soil samples are regularly taken at the plant and that local residents are in no danger.