PA sources claim ceasefire went into effect at 4:30 a.m. Earlier, rocket barrage fired toward southern Israel.

Hamas' television and other Palestinian Arab sources reported overnight Sunday that a ceasefire had been reached with Israel, and that it went into effect at 4:30 a.m.

However, Israel has not confirmed this.

Earlier, the rocket fire on Israel continued, as “Red Color” sirens were sounded in Ashkelon and in the regional councils of Eshkol, Hof Ashkelon, Sdot Negev and Bnei Shimon.

So far there have been no reports of rockets exploding or being intercepted. The IDF said the details are under investigation.

Before midnight, there had been reports claiming that Egypt and Qatar had brokered a ceasefire scheduled to take effect at midnight on Sunday.

However, a Palestinian Arab source later said that "as of now there is no calm. Israel is delaying the implementation of the understandings reached in the past, but seeks to achieve calm in return for calm."

The source added that a truce is conditional on progress on the ground and will not occur until Israel fulfills all the demands of the factions. His remarks were quoted by Channel 13 News.

Meanwhile, the IDF continues to attack terror targets in Gaza in retaliation for the rocket fire.

On Sunday evening, IDF fighter jets targeted the office of Tawfiq Abu Naim, Minister of the Interior and Head of the Palestinian Preventive Security in Hamas' Political Bureau in Nuseirat.

Abu Naim had been incarcerated in Israel since 1991 and was released as part of the 2011 Gilad Shalit prisoner exchange.

Following his release, Abu Naim joined the Hamas leadership. He oversees security measures in the Gaza Strip – including ongoing security, as well as Hamas’ Police forces (forces deployed for terror purposes).

Earlier on Sunday, IDF fighter jets targeted a seven-story building disguising an underground offensive terror tunnel in the Al Farkan neighborhood in Gaza City.

As the building was being built in 2010, Hamas took control over it. The terror organization took advantage of the building being built in order to dig a significant, multi-branch tunnel network beneath it. The building is located adjacent to a school in the heart of a civilian neighborhood.

Hamas uses this building for various operational activities, including the protection and concealment of terror infrastructure while completely disregarding its location in the heart of a residential neighborhood.

IDF Spokesman Ronen Manelis said on Sunday evening that IDF fighter planes had completed an assault on about 40 terror targets of the Hamas and Islamic Jihad terrorist organizations throughout Gaza.

The targets included underground infrastructures, weapons warehouses, military compounds, rocket-launching positions, observation posts, and more. Since Saturday, some 320 terrorist targets have been attacked and IDF attacks continue according to plan.