The mysterious killing last week of a top Syrian general and key aide to Bashar al-Assad, the Syrian president, has sparked intense speculation about internal feuding within the regime’s intelligence apparatus.

Syria is at a critical juncture as it pursues indirect peace talks with Israel and a closer relationship with the West, while attempting to maintain its long-standing regional alliances with Iran and the militant Shia Hezbollah of Lebanon.

General Mohammed Suleiman, one of Mr Assad’s closest confidantes, was shot dead on Friday at his chalet in the prestigious Rimal al-Zahabieh, Arabic for “Golden Sands”, seafront resort, 9 miles north of Tartous on the Mediterranean coast. A sniper, apparently located out at sea, shot him in the head, neck and stomach and he was pronounced dead at a hospital in Tartous.

Assassinations of leading regime figures are rare in Syria, and the Syrian authorities have scrambled to prevent news of the incident from leaking. Adding to the whirlwind of speculation is that General Suleiman was an Alawite, the same religious sect to which the Assad family belongs and which forms the backbone of the nominally secular regime in Damascus.

Mr Assad, who is said to be deeply upset by the murder, continued with his schedule over the weekend, travelling to Tehran for talks with his Iranian counterpart, Mahmoud Ahmadinejad.

General Suleiman’s relationship with Mr Assad stems from the mid-1990s when the latter abandoned his ophthalmology studies in London and returned to Damascus from London on the death of his elder brother Basil in 1994, who was being groomed to succeed their father, Hafez al-Assad, as head of state.

Nicknamed “the imported general” because of his fair complexion and foreign looks, General Suleiman was chief military aide to Mr Assad in the late 1990s with additional important posts overseeing weapons research and development and army recruitment among others.

After Mr Assad became president in 2000, General Suleiman ran his intelligence affairs, and is reported to have handled the transfer of weapons from Syria to Hezbollah in Lebanon.

The link with Hezbollah could be connected to General Suleiman’s assassination, according to a well-placed Syrian source. The source told The Times that General Suleiman’s murder could be retribution for the sacking of top intelligence officers following the assassination in February of Imad Mughniyeh, Hezbollah’s military commander who died in a car bomb explosion in a Damascus suburb.

According to the source, the heads of several Syrian intelligence agencies were quietly replaced or had their powers stripped from them after the assassination. “The demoted intelligence chiefs may have met and decided on revenge,” the source said.

Whether General Suleiman was killed by a clique of disaffected intelligence officials or not, there is no shortage of alternative theories for his death.

Israel, which is holding its first indirect peace talks with Syria in almost a decade, has not commented on the assassination. It has demanded Syria cut its close ties with the Jewish state’s main enemy Iran, while Syria is demanding the return of the Golan Heights, captured in the Six Day War in 1967.

Meir Javendanfar, a specialist in Iranian intelligence, said the general was the liaison officer between the Syrian regime and Hezbollah, and noted that his Iranian counterpart, General Ali al-Asgari, had defected to the United States last year, severing key links between the Lebanese organisation and its backers.

“The assassination of Suleiman, Mughniyeh and the defection of General Ali al-Asgari sends a very strong message first and foremost to Hezbollah, and then to its allies in Iran and Syria that their activities and relations with Hezbollah in Lebanon are being watched,” he said. “It also says that the ranks of their intelligence organisations have most probably been infiltrated, and that a renewed conflict initiated by them would not be in their best interest, at least militarily.”

Another theory was aired by Sheikh Abdullah al-Raghib al-Hamed, a Syrian opposition leader, who told the Israeli news website Ynet that the assassination had been ordered from the very top of the Syrian regime as part of a cover up to hide its own implication in the 2005 Beirut bomb attack that killed Rafik Hariri, a former Lebanese prime minister and an opponent of Syria. Syria was widely blamed for the murder, and outrage sparked by the explosion forced Syria to withdraw troops that had been stationed in Lebanon since 1976.

"The area in which he was killed is surrounded by sensitive military facilities belonging to the Syrian army's intelligence, and it is very well secured,” said Mr al-Hamed, of the Syrian Democratic Coalition. “The fact that a sniper shot him is more evidence that the regime did it. The regime's goal is to get rid of anyone who could arrive at an international court and incriminate Assad.”

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