Conflict in Syria burst into neighboring Lebanon and Turkey on Monday, with one Lebanese cameraman killed and at least four people injured in fighting on the Syria-Turkey border.

The attacks, on the eve of a deadline under a fading U.N.-backed deal for ­Syrian troops to withdraw from cities and cease hostilities amid a widespread uprising, risked bringing the Syrian conflict to what the Turkish government called a “new stage.”

With the populations in neighboring countries divided between those who support the opposition in Syria and those who hope that embattled President Bashar al-Assad will remain in power, some fear that the conflict could expand across the region and widen political, ethnic and religious fault lines.

“I think we can expect more violence along the borders. I think that’s going to be the new normal,” said Shadi Hamid of the Brookings Doha Center in Qatar. “The more refugees there are trying to escape, the more skirmishes there will be.”

Activists have reported heavy casualties in recent days, with 84 civilians killed Monday, according to the Britain-based Syrian Observatory for Human Rights, along with 19 members of the security forces and eight defectors. Hopes are rapidly dimming that a six-point peace plan that U.N.-Arab League envoy Kofi Annan negotiated with Syrian authorities can halt the violence.

Syria map (The Washington Post/The Washington Post)

U.S. State Department spokeswoman Victoria Nuland said Monday that the incidents were “another indication that the Assad regime does not seem at all willing to meet the commitments that it made to Kofi Annan. Not only has the violence not abated, it has been worse in recent days.”

Nuland added that the Syrian government was trying to “stall for time” with its last-minute demand for a written guarantee that opposition forces will disarm before it withdraws troops from cities and towns.

Regional, U.S. responses

Turkey, a NATO member that shares a 550-mile-long border with Syria, has resisted direct involvement in the conflict, even as its government has condemned Assad.

But Assad has supporters in Turkey and in Lebanon, where Hezbollah, the dominant Shiite militia and political party, has long been allied with the Syrian leader and his Shiite-linked Alawite sect. Hezbollah’s chief political rival, former Lebanese prime minister Saad Hariri, has called for Assad to step down.

In Iraq, dominant Shiites fear that an Islamist Sunni government in Syria would build alliances with Iraq’s disgruntled Sunnis. Meanwhile, Iran, whose Shiite leaders are Assad’s staunchest allies, has seen its long-nurtured and highly profitable relationship with Turkey shaken over its stance on Syria.

Turkey has resisted allowing its territory to be used for any intervention in Syria without international legal authorization, ideally with a U.N. Security Council resolution.

Saudi Arabia and three other Persian Gulf countries have agreed to give the opposition Free Syrian Army a stipend of several million dollars a month, to be used to pay fighters and to buy weapons in the black market.

In Washington, White House spokesman Jay Carney said that the Obama administration “strenuously and strongly condemned” the attacks inside Turkey and Lebanon but that its objection to “providing military aid has not changed.” The administration has said that it will continue to apply diplomatic and economic pressure on Assad while supporting Annan’s efforts. Annan has scheduled a Tuesday visit to Syrian refugee camps in southern Turkey.

Administration officials have expressed hope that Assad’s failure to comply with the Annan agreement will persuade Russia and China, which vetoed previous Security Council resolutions, to change their minds. Syrian Foreign Minister Walid al-Moualem arrived in Moscow on Monday for a meeting with Russian Foreign Minister Sergei Lavrov.

Attacks along borders

The violence Monday came less than two weeks after heavy fighting on the Syrian side of the border threatened to spill into the Qaa area of Lebanon.

In Lebanon, Prime Minister Najib Mikati used Twitter on Monday to express condolences for the death of Ali Shaaban, part of a three-man crew with Lebanese television channel al-Jadeed, in the Wadi Khaled area of Lebanon on the northern border with Syria.

The two surviving journalists said in interviews with Lebanese media that they were in a car in Lebanon, filming and taking notes, when men in civilian clothes began shooting at them from the Syrian side of the border and continued to fire for two hours. Lebanese security forces rescued them, the journalists said.

One of them, Hussein Khrais, said in a telephone interview that he was unable to ascertain whether the attackers were armed opponents of the Assad regime or Syrian government forces.

In Turkey, violence broke out as dozens of Syrians — some wounded — sought to become the latest of more than 20,000 refugees to flee into the neighboring country, crossing near the Turkish village of Kilis, north of the Syrian city of Aleppo.

According to a Turkish Foreign Ministry spokesman, the refu­gee group was spotted making its way to the border in the morning. Several Syrian nationals, along with a Turkish police officer and a Turkish translator, approached the area to help them. As the two groups met at the border, they were fired upon by unidentified gunmen in Syria. Two Syrian refugees, the police officer and the translator were injured.

“We summoned the Syrian charge d’affaires in Ankara and told him that every Syrian within Turkish territory was under Turkish protection, and we urged him that the fighting on the other side of the border stop,” said the spokesman, who did not give his name. “We said that if this repeats, we will take necessary measures.”

Syrian officials did not comment on the incidents, but a state news agency quoted a “media source” as saying that the al-Jadeed team came under attack from a terrorist group that also fired on Syrian troops. Syrian officials have repeatedly blamed violence on terrorists and foreign groups.

DeYoung reported from Washington. Special correspondent Suzan Haidamous in Beirut contributed to this report.