Palestinian militant group Islamic Jihad has entered a second conflict with Israel in less than a year, with experts saying the Iran-backed movement is balancing competing interests as it insists on armed resistance.
According to the Israeli army, the Gaza Strip-based group has fired more than 860 rockets at Israel from the coastal enclave since Wednesday, a day after Israel killed three of the group's commanders in a barrage of air strikes on the territory, controlled by Hamas.
Israel charged that two of the three -- Jihad Ghannam and Khalil al-Bahtini -- were directly involved in rocket attacks on Israel a week prior, while the third -- Tareq Ezzedine -- was working to develop rocket-firing capabilities in the occupied West Bank.
At least 31 Palestinians, among them militants and civilians including children, have been killed in the latest violence, while one person was killed in Israel.
- Growing popularity -
The group was established in 1981 by students at the Islamic University of Gaza.
Unlike Hamas and Fatah, which governs the West Bank through the Palestinian Authority (PA), Islamic Jihad refuses to participate in politics. The group rejects the Oslo Peace Accords, which established the PA, insisting armed struggle is the only path forward for Palestinians.
The group has continued to "emphasise the need for armed struggle", according to Erik Skare, a researcher at the University of Oslo and author of a book on the group.
"Islamic Jihad has grown significantly since 2007 precisely because there has been this void in the Palestinian resistance (to Israeli occupation), and unlike Hamas and Fatah it has been unencumbered by the responsibilities of governance," he said.
- Group origins -
The group was founded and led by enigmatic writer and doctor Fathi Shaqaqi until 1995, when he was assassinated in Malta by a hit squad sent by Israel's spy agency, the Mossad.
Like Hamas, Islamic Jihad was born out of the Muslim Brotherhood, an Islamist movement established in Egypt last century.
In 1992, Islamic Jihad founded its armed wing, known as the Al-Quds Brigade.
Designated as a terrorist organisation by the United States, the European Union and others, Islamic Jihad claimed responsibility for multiple suicide bombings targeting Israelis, notably during the second Palestinian intifada, or uprising, from 2000 to 2005.
One of the group's most prominent attacks was in 1989, on a bus travelling between Tel Aviv and Jerusalem that killed 16 people.
"Don't let the name fool you," said Skare, who said the group is more than just a jihadist movement. He noted that, unlike Hamas, many of its social policies are secular rather than Islamist.
"Islamic Jihad never cared about what clothes you were wearing, or if an unmarried couple were holding hands, all they cared about was that you were pointing a rifle at the Israeli occupation," he said.
The group's current leader Ziyad al-Nakhala was first arrested in 1971 as a member of the Arab Liberation Front -- a secular nationalist movement, Skare added.
- Relations with Hamas -
Despite similar origins, relations between Hamas and Islamic Jihad have occasionally frayed in recent years.
Islamic Jihad "is quite aware it cannot afford to alienate Hamas, it depends on the goodwill of Hamas" to operate, said Skare.
Hamas has governed Gaza since 2007 and provides Islamic Jihad sanctuary in the territory.
Last August, Hamas stayed out of three days of fighting between the group and Israel that left 49 Palestinians dead, a decision that divided Palestinian opinion.
A poll by the Palestinian Center for Policy and Survey Research following the fighting showed 50 percent of Palestinians agreed with Hamas's decision and 37 percent disagreed.
That conflict prompted rare public criticism of Islamic Jihad on social media, with errant rockets thought to have killed Palestinians.
Israeli military officials have stressed Hamas's lack of involvement in the current round of fighting.
"Hamas is not reacting, I'm putting aside declarations, we are dealing with actions," a senior Israeli military official told journalists on Wednesday.
- Israel 'united' factions -
If relations between the two were fraying, disagreements will have been temporarily forgotten in the days since Israel began air strikes, said Tahani Mustafa, an analyst at the International Crisis Group.
Israel's targeted killing of the three Islamic Jihad commanders on Tuesday was a "provocation" which "has inadvertently united the factions", she added.
"Hamas has found itself in a situation where, because of the blatant nature of Israel's provocation, it has to support Islamic Jihad -- even when it did not do so initially -- or risk losing credibility as a resistance organisation," Mustafa said.
According to Skare, Islamic Jihad now faces a dilemma, between being "a principal defender of Palestinian rights -- continuing to escalate with rocket fire and counter-bombings from Israel -- and not alienating Hamas".
"It's a balancing act," he said.
