Syrian government aircraft scattered leaflets over the northern city of Idlib on Wednesday demanding rebels surrender, as the two sides battled for control of a highway the regime uses to transport weapons from a coastal stronghold to its troops fighting in opposition-held areas in the north.

The battle for the highway leading from the mountainous Latakia province along the Mediterranean coast into the neighboring province of Idlib is crucial to rebel efforts to retain control of the villages and towns they hold.

They dynamited a highway bridge near the city of Jisr al-Shughour, and demolished other parts of the road, said Fuad al-Deek, an activist via Skype, based in Idlib province. Syrian troops fired mortar shells and conducted airstrikes to try dislodge the rebels, according to the British-based Syrian Observatory for Human Rights, which has a network of activists on the ground.

Idlib holds strategic value to the rebels because it borders Turkey, which has been a critical source of weapons shipments and other supplies. Latakia province, meanwhile, is predominantly home to members of the president's Alawite sect, an offshoot of Shiite Islam.

Syria's conflict began in March 2011 with largely peaceful protests against Assad's rule but escalated into a civil war in response to a brutal government crackdown. The conflict has since taken an increasingly sectarian bent, with mostly-Sunni rebels assisted by foreign fighters. Assad's forces are bolstered by fighters of the Lebanese Shiite group Hezbollah.

Al-Deek said the rebels fighting for the Idlib highway were from two Islamic brigades, Suqour al-Sham and Ahrar al-Sham. He said they were struggling to obtain weapons to keep up their fighting, despite a recent influx of arms from Gulf Arab states.

In recent months, rebels have accessed more powerful weaponry, including anti-tank missiles and surface-to-air missiles, likely supplied by Qatar and Saudi Arabia.

The U.N. estimates that more than 93,000 people have been killed in Syria since the anti-Assad revolt began in March 2011. With so much blood shed and the country still contested, the regime's call Wednesday to surrender was highly unlikely to find any takers on the rebel side, either Syrians or foreign fighters.

One of the leaflets dropped in Idlib and addressed to foreign fighters read: "Abandon your weapons and return to your family."

The battle for Idlib province is one of a series of flashpoints as government forces push their offensive against the rebels on several fronts. The British-based Observatory also reported fighting in the northern province of Aleppo, in towns on the outskirts of Damascus as well as in the southern province of Daraa.

In the central city of Homs, Syrian troops backed by Hezbollah fighters were encircling the neighborhoods of Khaldiyeh and Bab Houd in the central city of Homs. Rebels have held those districts for the past year.

"The war here is now from building to building. They are trying to take the area a block at a time," said Homs-based activist Tariq Badrakhan via Skype. He added that Syrian forces were "cleaning" the area of rebel fighters by firing mortar shells at buildings.

Hundreds of thousands of Syrian civilians have been internally displaced because of the more than two-year conflict, and the U.N. estimates that another 1.7 million Syrian refugees have fled to neighboring Jordan, Turkey and Lebanon, many of them children.

On Tuesday, the U.N. Humanitarian Chief Valerie Amos warned that Syrian refugees in Lebanon could double in number to one million by the year's end, forming one-fifth of Lebanon's population of 4.5 million.

Amos said the international community has so far been sluggish in its response to aiding Syrian refuges. Amos said humanitarian organizations and the Lebanese government had only received 15 percent of a $1.7 billion appeal to assist refugees in Lebanon and the communities aiding them.

"If you have thousands of refugees crossing the border every day, it's a huge burden not just on the country but also on the people who are hosting the refugees," Amos said.


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