An Islamic jihadi group based in Egypt's Sinai has posted a video showing it carried out the cross-border attack in June that killed one Israeli at a border barrier construction site and raising doubts over Egypt's security control over the desert peninsula.

Since the overthrow of U.S.-aligned Egyptian President Hosni Mubarak in February 2011, the security grip has loosened over Sinai and groups of militant Islamists have spread across its north, attacking police stations and the pipeline that exports gas to Israel and Jordan.

A video posted online on Friday featured members of a new group named Magles Shoura al-Mujahddin wearing military outfits and choosing as their target an Israeli security patrol and a border town.

Video:

The men who, according to the video, carried out the attack were identified as Egyptian Abu Salah and Saudi Abu Hozaifa. They said they sought revenge for "Muslims' blood" and dedicated the attack to Ayman al-Zawahri, al-Qaida's leader.

"We will head shortly to execute a double suicide operation targeting the Jewish enemy forces on the Egyptian borders," Abu Salah said, reading from a piece of paper, before the attack. In the background was a black flag covered with religious slogans.

Israeli officials said soldiers killed both attackers.

Another jihadi group named Ansar Bayt al-Maqdes claimed responsibility for gas pipeline blasts in an online video last week.

Prime Minister Benjamin Netanyahu said in April that Sinai was becoming a lawless “Wild West," but his government had since signaled more confidence in the new Egyptian government's ability to restore order.

Egyptian security sources said they were investigating information in the videos and were aware of the existence of some jihadi elements but had no information on these two groups.

"These groups might be very small jihadi cells in Sinai," a security source told Reuters.

In the video, jihadis were seen monitoring the border spotting Egyptian and Israeli army sites before identifying a weak point along the border and choosing two Israeli Jeeps and a border town on the Israeli side as their targets.

The attackers were then instructed on the plan using a model of the area and were trained on making bombs and using live ammunition in a desert.

Egyptian security officials said it was unclear where the training took place.

Experts say that militant groups in Sinai are not directly affiliated to al-Qaida but are seeking to be so.

The open desert border between Israel and Egypt was relatively quiet for three decades after the two countries signed a peace treaty in 1979. But Israel says that since the fall of Mubarak, Cairo has lost its grip on the Sinai.

In April, Israel said a rocket fired from the Sinai hit the resort of Eilat, causing no injuries, while last August cross-border infiltrators shot dead eight Israelis. Israeli soldiers repelling the attack accidentally killed five Egyptian guards.

Mubarak was succeeded by Mohammed Morsi of the Muslim Brotherhood, which is ideologically hostile to the Jewish state and linked to the Hamas Islamists who run the Gaza Strip, the Palestinian territory that also abuts Sinai.