Police are investigating the latest animal deaths in Indonesia's largest and problem-plagued zoo.
Zoo spokesman Agus Supangkat said that an 18-month-old male African lion has been found hanged on a steel cable inside its cage. Days earlier, on Sunday, a five-year-old wildebeest died of a suspected stomach problem due to hot weather and humidity.
Police are investigating how the lion became trapped by the cable, which is used by zookeepers to open the cage.
The Surabaya Zoo in East Java's capital has been criticised over the deaths of scores of animals, including another African lion and a Sumatran tiger, in the last few years.
Built over a century ago under Dutch colonial rule, it houses some 3,500 animals, among them five African lions and a sole female wildebeest.