Residents inspect damaged cars after two rockets hit houses and cars in the Mar Mikhael area, a southern suburb of Beirut, Lebanon on May 26. (Wael Hamzeh/EPA)

Two rockets struck near Hezbollah’s stronghold in southern Beirut on Sunday, evidence of Lebanon’s increasing entanglement in the Syrian civil war as the Shiite movement sends militants to back President Bashar al-Assad.

The strikes, which injured four people, appeared to be a warning shot to Hezbollah, coming just hours after its leader, Hasan Nasrallah, said his militants would back the Syrian government to victory. The spillover adds urgency to efforts by Russia and the United States to organize peace talks to end the conflict, which Damascus confirmed Sunday it would attend “in principle.”

With Lebanese politics sharply divided between those who support the Syrian government and those who oppose it, Syria’s smaller neighbor has been blighted by clashes since the uprising over the border in Syria began two years ago. However, tensions escalated last week, with clashes between pro- and anti-Assad factions in the northern city of Tripoli claiming at least 30 lives.

Iran-backed Hezbollah’s entrenchment in the battle against a largely Sunni rebel force also raises fears that the conflict will become a wider regional struggle between Sunni and Shiite Muslims.

Sunday’s rockets fell in the largely Shiite district of Chiyah, which abuts Dahieh, home to Hezbollah’s headquarters. The first struck a car sales yard, pockmarking vehicles with shrapnel and injuring four Syrian workers. Shortly afterward, a second rocket hit an apartment roughly a mile away, smashing into the living room and leaving it strewn with rubble and glass.

Hussam Hussein, 32, was asleep with his pregnant wife in the next room when the rocket hit and was in no doubt why the area was targeted.

“It’s because we love Hasan Nasrallah,” he said.

Interior Minister Marwan Charbel said the rockets were launched from a “remote location” southeast of the site, giving no further details.

Over the past week, Hezbollah led an effort with Assad’s army to push rebels out of the Syrian town of Qusair, near the Lebanese border. Nasrallah argued Saturday that it was Hezbollah’s duty to cross the border to fight what he branded as an extremist opposition movement, before it attempts to destabilize Lebanon.

The Free Syrian Army has threatened to retaliate against Hezbollah.

In a video posted online last week, Col. Abdul Jabbar Akaidi, a senior commander in the Free Syrian Army in Aleppo, announced his departure for Qusair to fight Hezbollah forces.

“I will shell your citadels in Dahieh, God willing, as long as you keep attacking the Syrian people,” he said. “We used to say, ‘We’re coming to get you, Bashar,’ and now we will say, ‘We’re coming to get both of you, Bashar and Hasan Nasrallah.’ ”

However, Salim Idriss, the leader of the rebels’ Supreme Military Council, denied his group had any involvement in the rocket attack during an interview with al-Arabiya television Sunday.

Lebanon is not the only nation struggling to insulate itself from the Syrian conflict. Jordan is in talks to secure Patriot missile batteries to secure its territory, after a similar move by Turkey, Agence France-Presse reported Sunday.

“Jordan wishes to deploy Patriot missile batteries in order to boost its defense capabilities and help protect the country,” Information Minister Mohammad Momani said. “We are currently at the stage of talks with friendly states.”

With the Syrian regime indicating that it will attend peace talks, the focus turns on the Syrian Opposition Coalition, which has been meeting in Istanbul to decide its stance on attending and to vote on a new leader. However, what was meant to be three days of talks ending Saturday may now stretch to six days.

Louay M. Safi, a spokesman for the group, said the reason for the delay was disagreement over whether the group should be expanded to include a faction of 20 new members led by veteran opposition figure Michel Kilo. A proposal is being pushed by Western nations, including the United States, to water down Muslim Brotherhood influence.

Safi said there was a “general acceptance” among the opposition to attend the peace talks, but only if they take place with a clear commitment to a transition of power.

But, as Syrian Foreign Minister Walid al-Moualem confirmed that his government would “in principle” attend peace talks, he added: “No power on Earth can decide on the future of Syria. Only the Syrian people have the right to do so.”

Ahmed Ramadan contributed to this report.