BEIRUT — Rebels captured a major army post in the southern city of Daraa Friday after nearly two weeks of intense fighting, as battles raged between troops and opposition forces in the province that borders Jordan, activists said.

Daraa, the provincial capital of a region that carries the same name, is the birthplace of the uprising against President Bashar Assad that started 27 months ago. Rebels hope to one day launch an offensive from the area to take the capital, Damascus.

The Britain-based Syrian Observatory for Human Rights, which has a network of activists around the country, said Islamic militants led by members of the al-Qaida affiliate Jabhat al-Nusra, or the Nusra Front, captured the checkpoint after a two-week siege.

It said rebels blew up a car bomb Thursday killing and wounding a number of soldiers then stormed the post, made up of two of the highest buildings in the city.

"This post is very important because it overlooks old Daraa," said Rami Abdul-Rahman, who heads The Observatory. He added that the capture opens the way for rebels to take the southern neighborhood of Manshiyeh that is close to the Jordanian border.

An amateur video posted by activists showed rebels blowing up one of the two buildings after putting explosives inside it.

"This is considered the most dangerous and powerful post in Daraa and the whole province," said a man whose voice could be heard in the video as smoke billowed from the building.

Another video showed four militants carrying Nusra Front black flag standing in front of the building saying it will be blown up, apparently to prevent the regime from using it in case its forces capture it again.

The videos appeared genuine and were consistent with other AP reporting of the events.

Earlier, the Observatory said intense shelling by Syrian government troops on the village of Karak in Daraa province killed at least 10 women and girls overnight.

Buoyed by an influx of fighters from the Lebanese militia Hezbollah and other foreign Shiite Muslim militants, the Syrian regime has grabbed the initiative in the more than 2-year-old conflict in recent weeks, capturing a strategic town near the border with Lebanon and squeezing rebel positions around the capital, Damascus.

It said two women were killed when a shell hit the home of a local rebel commander. The women killed were his mother and aunt, the Observatory said.

A video posted on an Daraa activist's Facebook page showed the bodies of the women and children allegedly killed in the shelling lying wrapped in blankets. Another video from the village showed residents carrying other wounded into vehicles as women and children wailed.

The videos appeared genuine and were consistent with other AP reporting of the events.

The United Nations has estimated that more than 6,000 children are among the some 93,000 people killed in Syria's more than 2-year-old conflict, which started with largely peaceful protests against the rule of President Bashar Assad. The uprising escalated into an armed rebellion in response to a brutal government crackdown on the protest movement.

In recent weeks, government troops have gone on the offensive against rebel-held areas to try to cut the opposition's supply lines and secure Damascus and the corridor running to the Mediterranean coast, which is the heartland of the president's Alawite sect, an offshoot of Shiite Islam.

Regime forces have also made inroads in the south. Syria's state news agency said Friday government troops were chasing "terrorist cells" in the city of Daraa as well as the surrounding countryside, including along the border with Jordan. It did not mention Karak.

SANA said 18 opposition fighters including Jordanians, a Saudi and a Chechen, were killed and weapons were seized. It did not refer to civilian casualties.

State-owned Al-Ikhbariya TV also reported that government forces seized a truck loaded with weapons and ammunition in the central Homs province apparently destined for rebel fighters. The truck included with anti-tank missiles, machine guns, shoulder propelled grenades and communication devices, the station said.

The United States and its allies recently said they will help arm the rebels amid reports that Washington's Gulf allies have already sent much-coveted anti-tank missiles to select groups of fighters. The U.S. is still trying to sort out which rebels exactly will be given weapons and how, fearing that advanced arms may fall in the hands of Islamic extremists in the rebel ranks.

Meanwhile, the Observatory said a rare attack in Damascus's Old City Thursday was caused by an explosive device planted near a Shiite charity organization. The attack, which killed four people, was first believed to be a suicide attack near a church.

State media showed pictures of the body of the suspected suicide bomber in the ancient quarter. Residents had disagreed on the target of the attack but a government official also said a bomber wearing an explosive belt blew himself up near the Greek Orthodox Church.

Abdul-Rahman, the director of the Observatory, said investigation by activists on the ground indicated that a device was planted near the Shiite charity, and it blew up when this man was walking past. The Observatory originally reported that the explosion was caused by a suicide bomber. The church and charity are only around two dozen meters (yards) apart.

The conflict has increasingly taken on sectarian overtones. The rebels fighting to remove Assad are largely Sunnis, and have been joined by foreign fighters from other Muslim countries. The regime of Assad is led by the president's Alawite sect and his forces have been joined by fighters from Lebanon's Shiite Hezbollah militant group, a factor that has helped fan the sectarian nature of the conflict.

In an apparent snub to the targeting of a religious institution, The main opposition group, the Syrian National Coalition, said in a statement Friday that it "rejects" actions that violate the unity of Syrians and fuels sectarian strife, blaming the regime for attempting to incite it.

"The unfortunate practices of various individuals do not reflect the true values of the revolution," the statement said. "The Syrian Coalition reiterates that those who commit crimes and infringe on international conventions will be identified, pursued and brought to justice."