GAZA CITY (AFP) — Hamas’s top military commander Muhammad Deif, whose wife and son were killed in an airstrike in Gaza, is Israel’s most wanted man who has defied assassination attempts for years.

In the war between Israel and Hamas, Deif has been a shadowy if hardline presence, refusing to countenance a truce until Israel ends its seven-year blockade of the Palestinian enclave to prevent the import of materials that could be used for weapons.

Born in the Khan Yunis refugee camp in southern Gaza in 1965, Deif has been involved in Hamas’s operations for more than 20 years, plotting suicide bombings inside Israel, kidnapping soldiers, firing rockets and helping plan the tunnels used to launch attacks.

He was appointed head of Hamas’s military wing, the Izz ad-Din al-Qassam Brigades, in 2002 after the death of his predecessor, Salah Shehade, in a raid.

Muhammad Deif

Muhammad Deif

It was the ultimate promotion and the climax of a two-decade career in terrorism.

His involvement with the Islamist movement in Gaza began in the 1980s when, as a biology student close to the Muslim Brotherhood, he headed the Islamists’ union at Gaza Islamic University.

With the eruption of the Second Intifada in 2000, Deif escaped — or was freed — from a prison run by Yasser Arafat’s Palestinian Authority.

His escape — or liberation, as it is unclear whether he was freed or not — angered the Israelis, who had had him in their sights for more than a decade by then.

Shortly after he was named Hamas’s military head, Israel launched its fifth bid to assassinate him in Gaza. That attack left him severely wounded, and some rumors suggested he had been left paraplegic, although these were never confirmed, largely due to the secrecy surrounding the details of his life.

Deif delegated the leadership of the brigades to his deputy, Ahmed Jaabari, thus earning the nickname the “cat with nine lives” among his enemies, and cementing his reputation inside Gaza.

Master of disguise

Only a few, poor-quality photographs of Deif are known to exist, the most recent taken some 20 years ago.

The mysterious commander uses no technology that might allow the Israelis to track him, a Hamas official told AFP.

He may have learned caution from the death of his mentor, Yahya Ayash, killed in 1996 by a mobile telephone booby-trapped with explosives by Israeli secret services.

Izz ad-Din al-Qassam Brigades's chief Muhammad Deif delivering a recorded address after a Hamas terrorist infiltration into Israel, July 30, 2014. (screen capture: YouTube/Gal Berger)

Izz ad-Din al-Qassam Brigades’s chief Muhammad Deif delivering a recorded address after a Hamas terrorist infiltration into Israel, July 30, 2014. (screen capture: YouTube/Gal Berger)

Deif’s real name is Muhammad Diab al-Masri, and he owes his nom de guerre, which is Arabic for guest, to his habit of constantly changing his location, the Hamas official said.

The elusive leader’s public statements are extremely rare. In 2012, he warned Israel against launching operation Pillar of Defense, which was aimed at halting rockets fired by terrorists in the Gaza Strip.

After the death of his mentor Ayash, who passed on his explosive-making expertise, he took on the role of “engineer for the Izz ad-Din al-Qassam Brigades,” the Israeli army says in its blog.

The Israelis see him as “the brains” behind the campaign of suicide bombings that targeted buses and public places in Tel Aviv and Jerusalem until 2006 and consider him “personally responsible for the deaths of dozens of civilians.”

“Muhammad Deif deserves to die just like (Osama) bin Laden. He is an arch murderer and as long as we have an opportunity we will try to kill him,” Interior Minister Gideon Sa’ar told Army Radio Wednesday.

He also played a key role in the strategic development of Hamas, the Israelis say.

They claim that Deif was among the terrorists “who designed the Qassam rockets” — the Islamist movement’s signature weapon with a range of eight kilometers (five miles) until Iran supplied them with more advanced weapons.