Human Rights Watch said on Thursday that Iran has hanged four Iranian Arab activists from Khuzestan province on terrorism charges and sentenced to death five others who could soon face the same fate.

Human Right Watch on Thursday said Syrian regime forces appear to be using Soviet-made cluster bombs against rebel hideouts in a mountainous region of Hama province.

Two videos posted online on Tuesday appear to show unexploded sub-munitions and a bomb canister in Jabal Shahshabu, northwest of the city of Hama, said the New York-based group.

A Palestinian militant from the ruling Hamas movement was killed and two others wounded on Thursday in an Israeli air strike on eastern Gaza City, medics said.

The attack targeted a training ground used by Hamas' armed wing, the Ezzedine al-Qassam Brigades, in the southeastern Zeitoun neighborhood of the city, they said.

Turkey said it has found no traces of explosives on the wreckage of a fighter jet it has claimed was downed by Syria, raising new questions about the incident that inflamed cross-border tensions.

"No traces of explosives or flammable products were found on the debris recovered from the sea," a statement from Turkey's general staff said on Wednesday, adding that other material was still being examined.

Egyptian President Mohammed Morsi said he and Saudi's King Abdullah held "fruitful" talks focused on regional stability, SPA news agency said Thursday after a late night meeting between the two leaders.

Our discussions were "fruitful and constructive and in the interest of Egypt, of Saudi Arabia and of the people of the region," Morsi told reporters in Saudi's southern port city of Jeddah at the end of Wednesday night's meeting.

Syria's ambassador to Iraq, Nawaf Fares, who announced his defection to the opposition, has been "discharged," the foreign ministry said on Thursday.

"The ministry of foreign affairs announces that Nawaf Fares has been discharged and has no relation with our embassy in Baghdad, or with the foreign ministry," it said in a statement.

The U.N. and Arab League peace envoy for Syria, Kofi Annan, said on Wednesday the U.N. Security Council was discussing what action it could take next to address the crisis.

"The Council is now discussing what the next steps should be and what action they can take," said the former U.N. chief. "We should hear something in the next few days."

Rebels and troops clashed in the Damascus district of Qadam on Wednesday as at least 52 people were killed in violence around Syria, the Syrian Observatory for Human Rights said.

Apart from the fighting in Qadam, hundreds of youths gathered late Tuesday in the capital's upmarket district of Mazzeh and chanted anti-regime slogans, it said.

Syrian authorities have arrested a prominent businessman and opposition figure on charges of inciting civil disobedience, a top human rights activist told Agence France Presse on Wednesday.

"Mohammad Bassam al-Malek, 65, was jailed on orders from the state prosecutor for inciting civil disobedience due to his role in a strike by merchants in May," activist Anwar Bunni said.

Amnesty International on Wednesday called on Bahraini authorities to release leading Shiite activist Nabil Rajab sentenced to three months in jail for posting tweets deemed insulting to Sunnis.

"Like many others in Bahrain, Rajab is a prisoner of conscience, jailed solely for peacefully exercising his right to freedom of expression," said Ann Harrison of Amnesty's Middle East and North Africa program.