BEIRUT - Syrian government forces battled rebels outside Damascus on Tuesday in what activists said was the worst violence in the suburbs of the capital since an uprising against President Bashar Assad began 16 months ago.Video published by activists recorded heavy gunfire and explosions. A trail of fresh blood on a sidewalk in the suburb of Qudsiya led into a building where one casualty was taken. A naked man writhed in pain, his body pierced by shrapnel.Samir al-Shami, an activist in Damascus, said tanks and armored vehicles were out on the streets of the suburbs and some activists reported that one tank had been blown up.The British-based Observatory, which has a network of activists across Syria, said security forces and armored vehicles stormed the neighborhood of Barzeh, an opposition toehold inside Damascus, and there were sounds of heavy gunfire.Daily death toll amountsThe revolt against Assad's rule has intensified in response to an army crackdown, becoming a civil war. At least 10,000 people have been killed since March 2011 according to the United Nations. Diplomats say the actual number is much higher.Fighting is now frequent in Damascus, once considered a bastion of Assad.The observatory said over 100 people had been killed in violence on Monday, including 65 civilians and at least 31 members of the security forces.The highest reported death tolls were in southern Deraa, where at least 18 were killed including a family of four who were executed, and in eastern Deir al-Zor, where 17 people lost their lives, the activist center said.Video shot by activists in the city of Homs showed detonations from heavy weapons and fiery plumes of black smoke rising over the rooftops of smashed and abandoned buildings.Aid workers were on their way back to Homs to try to evacuate trapped civilians and wounded, but negotiations are still under way to secure safe access, the International Committee of the Red Cross (ICRC) said in Geneva."We cannot foresee when the team will be able to do so." ICRC spokesman Bijan Farnoudi told Reuters.Aid workers have sought access to the flashpoint city since government forces and opposition groups agreed last week to the agency's request for a humanitarian pause in the fighting.SANA said members of the United Nations Supervision Mission in Syria (UNSMIS) toured Tartous province on Monday and "inspected the calm, security and stability prevailing".The 300-strong UN monitoring mission was suspended 10 days ago because it was considered too dangerous to carry on sending teams out to supervise a truce that exists on paper only.UN special envoy Kofi Annan, who crafted the failed ceasefire and monitoring plan in April, wants the five permanent members of the UN Security Council and governments with influence on Assad or the rebels to decide what to do next, at a meeting pencilled in for June 30 in Geneva.Annan says Assad's ally Iran should be at the table, but the involvement of Tehran is opposed by the United States, Britain and France.The Syrian state news agency SANA said "armed terrorist groups" had blocked the old road from Damascus to Beirut."The clashes led to the killing of tens of terrorists, wounding a large number of them, arresting others and seizing their weapons which included RPG launchers, sniper rifles, machineguns and a huge amount of ammunition," the agency said.Syrian state television said rebels had kidnapped four-star airforce general Faraj Shahadeh from his home in the heart of Damascus on Tuesday, and that a special forces unit was trying to rescue him. It gave no further details.The Syrian Observatory for Human Rights reported heavy fighting near the Republican Guard headquarters in Qudsiya, and in the Damascus suburbs of al-Hama and Mashrou' Dumar, just 9 km (6 miles) outside the capital.It said 38 civilians and 24 troops had been killed during the day across Syria.