BEIRUT (AP) - One of Syria's most powerful military officers was killed in fighting with al-Qaida-linked Islamic extremists in an oil-rich eastern province largely controlled by the rebels, Syrian state-run television said Thursday. The fighting came amid a new push to hold an elusive peace conference for Syria's civil war, with the government proposing the talks start late next month, though there was no sign the opposition would attend. Maj. Gen. Jameh Jameh was killed in the provincial capital of Deir el-Zour, where he was the head of military intelligence, state-run TV said. He was the most senior military officer to be killed in more than a year. The report did not say when or how Jameh was killed, only that he died "while he was carrying out his mission in defending Syria and its people." The Britain-based Syrian Observatory for Human Rights said Jameh was killed by a sniper bullet during clashes with rebels, including members of al-Qaida-linked Jabhat al-Nusra or Nusra Front. Jameh's cousin, Haitham Jameh, told Lebanon-based Al-Mayadeen TV that the general was killed when a bomb exploded as he led his troops in an operation in Deir el-Zour, site of more than a year of clashes between regime forces and rebel fighters, who control most of the province. He was the most powerful Syrian officer to be killed since a July 2012 bomb attack on a Cabinet meeting in Damascus killed four top officials, including the defense minister and his deputy, who was President Bashar Assad's brother-in-law. That attack also wounded the interior minister. Jameh played a major role in Lebanon when Damascus dominated its smaller neighbor. When Syrian troops withdrew from Lebanon in 2005, ending nearly a three-decade military presence, Jameh was in charge of Syrian intelligence in the capital, Beirut. He was among several top Syrian officers suspected of having a role in the 2005 assassination of former Lebanese Prime Minister Rafik Hariri. Syria denies any involvement in the slaying. Four members of the Syrian-backed Hezbollah were charged in 2011 by a U.N.-backed tribunal with plotting the attack that killed Hariri, though none have been arrested. Their trial is scheduled to start in January. A fifth Hezbollah member was indicted earlier this month. Mustafa Alloush, a senior member in Hariri's Future Movement, noted that Jameh was in charge of Beirut's security at the time of the assassination, and "it is difficult to believe that Hezbollah carried out such an operation without full coordination with Syrian intelligence." In Moscow, meanwhile, the Syrian deputy prime minister, Qadri Jamil, floated Nov. 23-24 as possible dates for talks on a political solution to the Syrian conflict, though there was no agreement on the ground rules for negotiations and the main Western-backed opposition hasn't decided whether to attend. U.N. Secretary-General Ban Ki-moon said Wednesday that efforts were intensifying to try to hold the Geneva meeting in mid-November. Ban did not provide specific dates, and it's not clear whether those provided by Jamil had been agreed to by any other parties. The talks have been put off repeatedly, in part because of fundamental disagreements over the fate of Assad. Many rebel fighters inside Syria flatly reject negotiating with Assad's regime. The next phase gets more complex and dangerous, however, when actual chemical weapons have to be destroyed - in the midst of full-blown war. Syria's revolt began in March 2011 with largely peaceful protests against the Assad regime before turning into a civil war. The Abu Dhabi-based channel said it lost contact on Tuesday with its reporter, cameraman and their Syrian driver. Associated Press writers Laura Mills in Moscow and Edith Lederer in New York contributed to this report.