Iran could launch a pre-emptive strike if Israel prepares to attack it, a senior Revolutionary Guards commander told broadcaster Al-Alam on Sunday, a day after his boss warned that conflict was inevitable.

Should Israel and Iran engage militarily, "nothing is predictable... and it will turn into World War III," Brigadier General Amir Ali Hajizadeh told Iran's Arabic-language television network.

Embattled Syrian President Bashar Assad's only sister, Bushra, whose husband was killed in a July bombing, is now living in Dubai with her children, Syrian residents told Agence France Presse on Sunday.

Bushra's husband General Assef Shawkat, an army deputy chief of staff, was killed along with three other high-ranking officials in a July 18 bombing at the National Security headquarters in Damascus.

Bombings in Iraq killed at least four people, among them two soldiers, and wounded at least six other people on Sunday, security and medical officials said.

A magnetic "sticky bomb" attached to a minibus exploded in Sadr City in north Baghdad, killing two people and wounding six, an interior ministry official said, while a medical source put the toll at three dead and eight wounded.

Syrian aircraft carried out strikes on rebel bastions across the country on Sunday, especially in the central province of Homs and Deir Ezzor in the east, a monitoring group said.

The Syrian Observatory for Human Rights said apartment blocks in Albu Kamal were targeted as rebels and soldiers fought battles on the ground in several districts of the town on the Iraqi border.

A Palestinian woman tried to stab an Israeli policeman on an east Jerusalem street on Sunday, apparently in protest at a US-made film which denigrates Islam, an Israeli police spokesman said.

"An Arab woman this morning tried to attack an Israeli policeman, who managed to control the situation and no one was injured," spokesman Micky Rosenfeld told Agence France Presse.

An Islamist militant group said it launched a deadly cross-border attack on Israel from Egypt's Sinai in protest at a U.S.-made film mocking Islam, SITE Intelligence Group reported on Sunday.

Ansar Bait al-Maqdis (Partisans of Jerusalem) termed the attack a "Disciplinary Invasion Against those who Dared Against the Beloved Prophet," the U.S.-based monitoring agency said, citing a statement posted on Islamist websites.

Syria's vast territory is increasingly outside the control of the regular military, whose aerial superiority is the last strength keeping the Damascus regime afloat, a rebel chief told Agence France Presse.

"With or without outside help, the fall of the regime is a question of months, not years," said Colonel Ahmed Abdel Wahab, who claims that he commands a brigade of 850 men in the Free Syrian Army (FSA).

The daughter of Iran's former president Akbar Hashemi Rafsanjani has been arrested and jailed under a six-month sentence for "propaganda against the regime," the Tehran prosecutor's office said in a statement carried by official media on Sunday.

"Faezeh Hashemi was arrested on Saturday evening to serve her sentence," the statement read, according to the official IRNA news agency.

Israel will not accept alterations to its 1979 peace treaty with Egypt, Israeli Foreign Minister Avigdor Lieberman said on Sunday, as ties between the two countries continue to fray.

"There is not the slightest possibility that Israel will accept the modification of the peace treaty with Egypt," Lieberman told Israeli public radio. "We will not accept any modification of the Camp David accords."

Libya's armed forces announced on Sunday that they had dislodged a militia from a military complex on the highway leading to Tripoli International Airport.

Commander in chief Yussef al-Mangush said on his Facebook page that members of the militia were arrested and that their weapons were confiscated.