In a shocking incident, two stray dogs entered the Delhi Zoo and killed three rare deer last month, officials have confirmed. The incident took place on November 12.

The dogs jumped over an eight-foot-high boundary wall and entered the deer enclosure. Two endangered hog deer and the only sika or Japanese deer at the zoo were found dead the next morning, the officials said. The guards were unaware of what happened during the night.

Zoo officials suspect that a mound of debris and garbage piled up against the wall outside the zoo enabled the dogs to jump over the high wall. The barbed over the boundary wall of the zoo is also broken at several places and needs to be fixed.

Zoo officials said that the municipal authorities have been asked to clear the garbage mound and the broken parts of the fence were also being fixed.

The Zoo authorities have ordered an internal inquiry into the incident.