Russian Foreign Minister Sergei Lavrov arrived in Riyadh for talks with his Arab counterparts in the Gulf on Wednesday that are expected to highlight differences on the conflict in Syria.

Lavrov began his visit by meeting with Saudi Foreign Minister Saud al-Faisal, an AFP correspondent reported.

Israel killed a top Hamas military chief in an air strike in Gaza on Wednesday and launched a military operation against the Palestinian enclave, prompting Hamas’ armed wing to warn that the Jewish state had opened "the gates of hell."

Egypt said it was recalling its ambassador over Israel's hit on a car in Gaza City that killed Ahmed Jaabari and his bodyguard, followed by more than 20 air strikes in Gaza that killed another six people and wounded 65, according to the Hamas health ministry and rescue services.

Four explosions which hit a small Israeli community along the Egyptian border on Wednesday are believed to have been caused by rockets fired from Sinai, an Israeli security source told Agence France Presse.

The incident took place in Bnei Netzarim which lies 1.5 kilometers (just under a mile) from the Egyptian border, and some five kilometers (three miles) from the southernmost tip of the Gaza Strip.

A Turkish court sentenced a Syrian national on Wednesday to over 12 years in prison for allegedly spying in refugee camps near the border with the conflict-wracked nation, the Anatolia news agency reported.

The court had initially sentenced Sbahi Hamdo and his Turkish accomplice to 15 years in prison for "gathering confidential state information with the aim of political or military espionage".

A meeting of the Syrian opposition hosted by the Qatari capital amounted to a "declaration of war," the country's deputy foreign minister, Faisal Muqdad, said on Wednesday, describing France's decision to recognize the opposition alliance as "immoral.”

"The Doha meeting was a declaration of war. These people (the opposition) don't want to solve the issue peacefully through the mechanisms of the U.N.," Muqdad told Agence France Presse.

Israel's foreign ministry has proposed in a policy paper "toppling" Palestinian president Mahmoud Abbas if a Palestinian bid for state observer status at the United Nations is approved later this month.

"Toppling Abu Mazen's (Abbas's) regime would be the only option in this case," the position paper obtained by Agence France Presse says. "Any other option... would mean waving a white flag and admitting the failure of the Israeli leadership to deal with the challenge."

A meeting in Tokyo later this month aimed at increasing pressure on the Syrian regime could include several Southeast Asian countries, Japanese officials said Wednesday.

The November 30 meeting will bring together senior government officials from the "Friends of Syria Group" supporting the Syrian opposition and will focus on making sanctions more effective, a foreign ministry official said.

U.S. Secretary of State Hillary Clinton Wednesday announced $30 million in extra humanitarian aid to those affected by the conflict in Syria, as she welcomed its new opposition coalition.

Clinton, in Australia for annual security and defense talks, said the formation of a new Syrian opposition coalition was "a good beginning".

Ten people were killed Wednesday when a rescue helicopter ferrying wounded people from a vehicle accident to hospital hit power lines and crashed to the ground in northeastern Iran, media reported.

Those who died included four members of the helicopter crew, five people who had been wounded in the minibus crash and a medic from the emergency services.

Syrian army tanks shelled a refugee camp and two nearby districts in southern Damascus on Wednesday as battles raged and warplanes bombarded a rebel-held northwestern town, a watchdog said.

The tanks were deployed at the Palestinian camp of Yarmuk overnight, as well as the nearby districts of Tadamun and Assali, said the Syrian Observatory for Human Rights.