BEIRUT (AP) — A barrage of rockets slammed into a contested district on the northeastern edge of Damascus, killing at least five people and trapping others under the rubble, while violence raged around suburbs of the capital, activists said Friday.

The attack on Barzeh, where rebels aiming to topple President Bashar Assad are known to operate, follows days of heavy fighting between the rebels and the military in the area.

Rebels have established footholds in districts on the edge of Damascus and in suburbs in the northeast and south, from where they fire mortars into the heavily guarded city. Despite their efforts, they have been unable to break the Assad regime’s tight hold in the capital.

The activists said several rockets exploded in a residential area in Barzeh district Thursday night and Friday morning. The opposition Barzeh Media Center and a militant website claimed the Syrian military fired 14 rockets, leaving people, including children, buried under the rubble.

It said three children, a woman and an elderly man were killed.

"The impact of the rockets was huge," said a Barzeh-based activist. "Several houses collapsed and others were set on fire," he said, speaking on condition of anonymity for fear of government reprisals.

Amateur videos posted online by activists showed what appeared to be destroyed and burning houses. Others showed men with a flashlight working to pull out a survivor from the rubble. The videos appeared consistent with AP reporting.

The Britain-based Syrian Observatory for Human Rights confirmed a barrage of shells hit Barzeh and said at least one person was killed and several others wounded. It said the nature of the attack and exact number of casualties was not clear.

Barzeh is close to Esh el-Wirwar, a suburb of Damascus predominantly inhabited by Alawites and Syrian army volunteers. Rebels frequently target the area with mortar shells.

The Syrian revolt started with largely peaceful protests in March 2011 but has developed into a civil war with increasingly sectarian overtones.

Sunni Muslims dominate rebel ranks, while the Assad regime is composed mostly of Alawites, an offshoot Shiite group to which the president and his family belong. More than 70,000 people have died in the conflict, according to the U.N.

Activists also reported fighting in many parts of the country, including the southern province of Daraa near the border with Jordan, where rebels have been making significant advances.

A Jordanian security official said Thursday the kingdom has tightened security along its 370-kilometer (230-mile) border with Syria, doubling the number of soldiers in the last two days. He declined to disclose the size of the force.

The stepped up security reflects the kingdom’s fears that the chaos from Syria’s 2-year-old civil war could lead to a failed state on its doorstep where Islamic militants have a free hand.

President Bashar Assad’s regime warned Thursday the kingdom is "playing with fire" by allowing the U.S and other countries to train and arm Syrian rebels on its territory.

The warnings followed statements from U.S. and other Western and Arab officials that Jordan has been facilitating arms shipments and hosting training camps for Syrian rebels since last October.