A leak prompted authorities to declare a seven-hour emergency at a nuclear power plant in southern Pakistan this week.

The leakage of heavy water was reported at the Karachi Nuclear Power Plant, known as KANUPP, late Tuesday.

Authorities say the emergency was declared immediately after the leak and the affected area was isolated. Officials said Thursday the situation was controlled and that the emergency is over. No damage or radiation has been reported.

The plant had been closed for maintenance earlier this month.

The facility is located on the outskirts of the southern city of Karachi and has been operating since 1971. The plant is capable of producing roughly 100 megawatts of electricity.