Park officials said they discovered carcasses of four adult gaurs in the wildlife rehabilitation areas of the Kuiburi national forest reserve this week.
The discovery of the latest dead gaur raised to total number of dead gaurs to 12 in two weeks.
Deputy director-general of the Department of National Parks, Wildlife and Plant Conservation Mr Thirapat Prayurasit said during the inspection of the scene that park officials decided to shut down some of the observation areas with two remained open _ the elephant and gaur observation site, and the Salad Dai site _ for safety reasons of tourists.
He said that park officials still could not yet establish the exact cause of the deaths whether they died of poisons or epidemic.
He said that officials would discuss with relevant government agencies to establish the cause to prevent the remaining gaurs in the forest reserve.
He added that autopsy result of the dead gaurs would be known in 7-8 days.