The fire followed an Israeli Air Force strike in Gaza, targeting a three-man Qassam cell spotted trying to fire rockets at Israel.
The Islamic Jihad said that the IAF fire "was carried out under the cover of the Israeli and Palestinian leaders' meeting in the UN… The enemy is using the renewed talks and political meetings to continue committing aggressive crimes against our people and the mujahedeen.
"Our people are used to paying for political talks with the blood of their sons," continued the statement. "This strike was a clear message from the enemy regarding the Palestinian people and their rights and was meant to pressure the Palestinians into making further concessions."
The Islamic Jihad "would retaliate on the killing of its operatives in the proper place and time," it ended.
Friday's IAF strike in the Tuffah neighborhood in east Gaza City was the first since the conclusion of Operation Cast Lead in January.
The IDF Spokesman's Unit confirmed the attack, saying that contrary to Palestinian reports, the cell was targeted near the northern Gaza neighborhood of Jabalya.
The operatives have been identified as Kamal Dahduch, son for former Jihad commander in Gaza Khaled Dahduch; Mahmoud al-Bana, brother of one of the group's military wing commanders and Muhammad Marshud.
Military sources noted that the cell was responsible for several rocket launchings at Israel, including firing at Sderot during Rosh Hashana.