Defense Minister Moshe Ya'alon ruled out on Monday any possibility of a prisoner swap deal with Hamas for the return of two Israelis who entered the Gaza Strip on their own accord over the past year, and called on the Gazan regime to release them. "Of course we are not talking about a deal. A deal is not on the agenda and we demand that Hamas returns them to us without conditions," Ya'alon said, speaking at a conference held by the Israel Democracy Institute and the Makor Rishon newspaper. Ya'alon said both Israelis suffered from mental issues, and that Israel attempted to covertly secure their release on humanitarian grounds in recent months. Prime Minister Benjamin Netanyahu said last week that Israel viewed Hamas as responsible for the safety of 26-year old Ethiopian-Israeli Avera Mengistu, and a Beduin Israeli who were missing in Gaza. State Comptroller Yosef Shapira was asked Friday to investigate why Netanyahu did not inform the security cabinet or Knesset Foreign Affairs and Defense Committee that there were two Israelis missing in the Gaza Strip for months.