WASHINGTON -- In October, Hassan Nasrallah, the leader of Hezbollah, delivered a rare speech to comment on rising rumors about the Lebanese Shiite group's involvement in Syria's ongoing civil conflict.
For weeks, reports had circulated that the bodies of dead Hezbollah fighters had been returning from the battleground in neighboring Syria.
Nasrallah, speaking via a remote transmission as is his custom, vehemently denied the reports. But he also didn't rule out the possibility of Hezbollah joining the battle in the future.
"As of now, we have not fought alongside the regime," he said. "We don't know about the future."
The battle lines in Syria fall neatly along sectarian lines, with most of the Syrian rebels being Sunni Muslims supported by the Sunni countries of the Arabian Gulf, while Syrian President Bashar Assad's regime is being backed by the Shiite government of Iran and by Hezbollah. The latter has been open about its support for Assad -- at least politically.
But since Nasrallah's speech, signs have been growing that Hezbollah's armed wing is being drawn directly into Syria's conflict, raising the specter of the violence spilling over into Lebanon.
Lebanese newspapers reported last week that a handful of Hezbollah fighters had been killed in a battle with Syrian rebels in Al-Qusayr, a Syrian town not far from Lebanon and heavily populated with Shiites.
And on Wednesday, a group of Sunni Syrian rebels made a public threat to bring the fighting to Hezbollah, giving the group 48 hours to cease its incursions into Syria before the rebels would retaliate.
The next day, a top Free Syrian Army commander reiterated the warning. "As soon as the ultimatum ends, we will start responding to [Hezbollah] sources of fire," Gen. Selim Idriss, chief of staff of the Free Syrian Army, told Agence France-Presse. "Hezbollah is abusing Lebanese sovereignty to shell Syrian territory and Free Syrian Army positions."
That deadline was set to end Friday, and there have been some early, unconfirmed reports of Syrian rebels attacking Hezbollah positions.
The reports of Hezbollah's incursions into Syria date back many months. However, in public remarks -- whether by official channels or through news reports -- Hezbollah party leaders and officers have always downplayed those stories and have spoken of their possible entry into the fighting as a reluctant and defensive measure. Officially, the group has called for the Lebanese government to become more involved in shaping a political settlement to the violence in Syria.
In his October address, for instance, Nasrallah denounced specific claims that a top commander with Hezbollah had died in a clash in a Syrian town not far from Lebanon, saying that the man had been killed in a weapons accident while helping guard a Lebanese border town.
"Abu Abbas is a commander of the group's infantry unit in the Bekaa," Nasrallah said, by way of explaining the commander's death. "He is then responsible for the Hezbollah members in that area, and because these border towns continue until this day to be attacked [by Syrian rebels], martyrs have fallen and Abu Abbas was one of them."
A pseudonymous Hezbollah commander undermined this claim in a recent New Yorker article, insisting that Abu Abbas had indeed perished in battle and that "a lot of bodies" have been coming back from the Syrian battleground.
But he also characterized the fight as the front line of a Shiite and Lebanese defense against a surge of Sunni Salafism pushed by the Syrian rebels and their allies in the Gulf. "You wait and see," he said. "You're going to have Salafists in Syria attacking the Golan Heights. What are you going to do then?"
His remarks echoed those of another unnamed Hezbollah fighter, who told McClatchy this week that while fighters had been going in and out of Syria in a supporting role, the extent of Hezbollah's involvement in the conflict was greatly exaggerated and remained focused on defending their own country from a flood of Sunni extremists.
The Free Syrian Army is not the only group to have launched broadsides against Hezbollah since the start of the Syrian uprising. Last September, a commander with an al Qaeda offshoot in Syria posted a message to online message boards denouncing the group for its reported involvement in the assassination of former Lebanese Prime Minister Rafik Hariri, and promising retaliation.
Late last year, the United States designated another Syrian rebel faction, Jabhat al Nusra, as a terrorist group for its ties to al Qaeda in Iraq.