Iraqi daily Azzaman quoted a Western diplomatic source as saying Thursday that the alleged Israeli attack on Syria reported on Wednesday caused heavy casualties among special Iranian Guards stationed at the Syrian facility. The source also said that the attack took place more than 48 hours before it was reported, eventually being leaked by Israel.The source for the story, who was interviewed by the paper in London, said that the report about a strike on a convoy to Lebanon was probably meant to divert attention away from the main objective of the operation, which used F-16 aircraft to fire at least eight guided missiles at the facility.The source also said that the base was heavily fortified and contained experts from Russia and at least three thousand Iranian Revolutionary Guards, who have been guarding the site for years. Many of these Iranian Guards suffered casualties.Israel most likely got its intelligence, said the source, from penetrating deep inside Iran and from other operations meant to penetrate Hezbollah.The report came as outgoing US Secretary of State Hillary Clinton said on Thursday that there are signs that Iran is sending growing numbers of people and increasingly sophisticated weaponry to support Syrian President Bashar Assad."It appears that they may be increasing that involvement and that is a matter of great concern to us," she told reporters as she prepares to step down on Friday. "I think the numbers (of people) have increased ... There is a lot of concern that they are increasing the quality of the weapons, because Assad is using up his weaponry. So it's numbers and it's materiel." Iran, Syria vow retaliation for attackTehran and Damascus on Thursday threatened an unspecified, “surprise” retaliation against Israel in response to the reported Israeli air strike on a Syrian weapons center the day before. The Iranian regime’s English-language mouthpiece, Press TV, quoted Deputy Foreign Minister Hossein Amir-Abdollahian as saying that the “strike on Syria will have serious consequences for Tel Aviv.”Syria issued its threat to retaliate through the country’s ambassador to Lebanon.Ali Abdul Karim Ali told a Hezbollah-run news website on Thursday that Damascus had the option of a “surprise decision” to respond to what it said was an Israeli air strike on a research center on the outskirts of the Syrian capital on Wednesday.“Syria is engaged in defending its sovereignty and its land,” he added, without spelling out what the response might entail.According to foreign sources, in 2007 Israeli jets bombed a suspected Syrian nuclear site, and no retaliation was forthcoming despite Syrian threats.Last week, the Associated Press quoted a senior adviser to Iran’s supreme leader as saying that any attack on Syria would be seen by Tehran as an attack on itself. The official, Ali Akbar Velayati, said the regime of Syrian President Assad was a central component of the “resistance front.”Report: Syrian regime transferred nonconventional weapons to HezbollahAlso on Thursday, the Saudi-based Al-Watan newspaper reported that the Syrian regime had transferred nonconventional weapons to Hezbollah.Al-Watan, quoting unnamed sources from the Syrian opposition, reported that Assad had been transferring weapons to Hezbollah since the beginning of 2012, including 2 tons of mustard gas and long-range missiles, capable of carrying chemical warheads and traveling 300 kilometers.Syrian opposition sources also claimed that the transfers to Hezbollah took place over 40 days, from mid-February to March 2012, the Saudi daily reported.The chemical weapons transfer to Hezbollah was carried out under the supervision of Syrian Brig.-Gen. Ghassan Abbas. The Syrian source said that it observed these transfers since the beginning of last year.The tankers drove through Damascus and Zabadani, and then through Sirghaya on the Lebanese border, carrying the chemical weapons in blue barrels labeled “Chlorine Acid.”They took the material to “Hezbollah warehouses and delivered it to a person nicknamed ‘Abu Talal,’ who was subordinate to the party leadership.”The report also said that some of the chemical weapons were stored in a warehouse at the Mezze military airport, as well as at other locations around Syria.The Syrian SANA news agency released a statement by the General Command of the Armed Forces, which sought to link the supposed strike to Israel’s support – and that of other countries – for the Syrian rebels.“Warplanes violated Syrian airspace on Wednesday at dawn and bombarded a scientific research center responsible for raising our levels of resistance and self-defense. This attack came after Israel and other countries that oppose the Syrian people utilized their pawns in Syria to attack vital military locations,” the statement said.General Command also said that the attack “martyred” two workers and wounded five others.The “research center” building was also destroyed. It went on to deny claims that the attack targeted a convoy headed for Lebanon.In addition, it stated, “The General Command said that it has become clear to everyone that Israel is the motivator, beneficiary and sometimes executor of the terrorist acts which target Syria and its resistant people, with some countries that support terrorism being accomplices in this, primarily Turkey and Qatar.”An article in the Lebanese Al-Akhbar daily claimed that Syria would probably have to respond against Israel this time around.Wednesday’s attack on Syria “is very different from all previous raids at every level, and a non-response this time around would mean the acceptance of a new equation that Israel is trying to impose, in the form of shackles on the regime’s freedom of action. It is likely that the regime will be unable to accept these constraints without risking its very survival. Based on this, the more logical question has to do with the manner, nature, and scale of the Syrian response,” the paper said.Hezbollah called it “a savage attack that carries out the Zionist entity’s policy, which aims at preventing any Arab and Muslim state from developing its technological and military capabilities,” according to its Al-Manar website.Reuters and Jerusalem Post staff contributed to this report.