Israeli jets struck several sites in Khan Younes and Rafah in the Gaza Strip early Tuesday morning, according to Palestinian sources.

Earlier, a rocket was fired in the direction of the Eshkol Regional Council, landing in open terrain. There were no immediate reports of injuries or damage.

The strikes came hours after the bodies of kidnapped Israeli teenagers — Eyal Yifrach, 19, Gil-ad Shaar, 16 and Naftali Fraenkel, 16 — were found partially buried in a field near the West Bank village of Halhul, north of Hebron.

The teenagers were kidnapped on the night of June 12 at a hitchhiking post outside the settlement of Alon Shvut in the Etzion Bloc south of Jerusalem.

The bodies were found at about 5:30 p.m. Monday, bound and partially buried, in an open field in a hard-to-access area. The site is less than 20 kilometers (12 miles) from where the teens had been abducted.

Israel is on the hunt for two Hamas men it says were behind the kidnappings, Marwan Kawasme and Amer Aby Aysha.

Since the start of Operation Brother’s Keeper to find them, 18 days of searches had seen the arrests of over 400 Palestinians, a majority of them members of Hamas.

On Monday, Hamas operatives launched a large volley of rockets which slammed into Israel, the first time in years the Islamist group has directly challenged the Jewish state, according to Israeli defense officials.

At least 16 rockets were fired at Israel Monday morning, most of them hitting open areas in the Eshkol region, the army said.

The security sources, who spoke on condition of anonymity, assessed that Hamas had probably launched the barrage in revenge for an Israeli airstrike several hours earlier which killed one person and injured three more.

A member of Hamas’s militant wing was killed in the attack, Gaza health official Ashraf al-Kidra said.

While Israel has maintained it holds Hamas responsible for all rocket attacks, officials have said that smaller groups, such as Islamic Jihad, are usually behind the rocket attacks, while Hamas squads generally attempt to thwart the rocket fire.

Hamas hasn’t fired rockets into Israel since Operation Pillar of Defense ended in November 2012, and has yet to take responsibility for this latest barrage.

The group fired hundred of rockets at Israel over eight days during Operation Pillar of Defense in 2012, as Israel carried out punishing strikes on the Palestinian enclave.

A broken window from a rocket strike on Sdot Negev Monday morning. (photo credit: Sdot Negev spokesperson)

A broken window from a rocket strike on Sdot Negev Monday morning. (photo credit: Sdot Negev spokesperson)

Officials said Monday’s rocket attacks, which appeared to deliberately target Israeli communities close to the border with the Gaza Strip, may have been intended to warn Israel against targeting Hamas operatives.

The army said in a statement that the Sunday night air raid was targeting terrorists “in the southern Gaza Strip, during​ their final preparations to launch rockets at civilian communities of southern Israel.”

“Hamas is responsible for the outrageous attacks originating from Gaza, and will be pursued as such,” IDF spokesman Lt. Col. Peter Lerner said.

The air force attack on Khan Younis Sunday night came minutes after Palestinians in the coastal enclave fired a volley of rockets at southwestern Israel. The Iron Dome defense system shot down two of the projectiles — Grad rockets — over Netivot. There were no reports of injury or damage in the rocket attack.

Early Sunday morning, air force planes struck 12 sites in Gaza in response to rockets fired over the weekend. Two rockets hit the town of Sderot, close to the border with Gaza, late Saturday, causing a massive fire that destroyed a paint factory.