According to Israeli intelligence evaluations, during the Gaza war this summer, Hamas cooperated with global jihadi elements who used the Sinai Peninsula to fire rockets on Eilat.
On July 15, terrorists in Sinai fired two rockets the Red Sea resort city, lightly wounding four residents and destroying a number of vehicles.
This cooperation between Hamas and terrorist rocket launchers in Sinai was viewed by Egypt as a hostile violation of its sovereignty.
Towards the end of Operation Protective Edge, Israel bombed global jihadi cells that planned on leaving Gaza with weapons and heading into Sinai to carry out attacks on Egyptian military targets, and to fire rockets at Israel.
Ansar Bayt al-Maqdis, the chief al-Qaida-linked group in Sinai, maintains strong links with the Gaza Strip, partnering up with groups such as the Popular Resistance Committees (PRC).
In the past, this allows Gaza terrorist groups - including Hamas - to 'sub contract' attacks on Israel away from the Strip, in order to protect the ruling Hamas regime from Israeli retaliation.
There are hundreds of Salafi-jihadis based in Gaza, and many of them move to and from Sinai, smuggling weapons and plotting attacks.
As a result, some in the defense establishment view Gaza and Sinai as interlinked sectors. The danger of these networks merging with the extensive jihadi networks in Syria is substantial.
While enforcing truces with Israel, Hamas has often signaled to the Sinai groups that they are free to attack Israel as they please away from the Gaza Strip.