How will Iran retaliate for killing of Ismail Haniyeh?

Iranian authorities declared that Israel will pay heavy price after the killing of Hamas Political Bureau ahairman Ismail Haniyeh.

"Our response to the assassination of Martyr Haniyeh will be regrettable and painful," chairman of the Iranian Parliament's National Security and Foreign Policy Committee Ebrahim Azizi said.

The farewell ceremony for the Hamas politburo chief was held in Tehran today. Yesterday, Iran has announced three days of public mourning.