BEIRUT: Activists said up to 106 people were killed across Syria Tuesday as security forces continued an onslaught on the central city of Homs. Dire accounts of the humanitarian toll of the crisis inside pockets of the besieged city prompted the Red Cross to attempt to negotiate a daily cease-fire to deliver aid.

The Local Coordination Committees – a ground network of activists – told The Daily Star that 101 civilians, including 10 children and five defected soldiers had been been killed. They said 35 people had been confirmed killed in Homs alone.

Rami Abdulrahman of the London-based Syrian Observatory for Human Rights said late Monday night they had identified 68 dead by name, including 31 people in Homs, adding that they were unable to confirm reports that another 22 bodies had been found in Homs.

“Without names and video, we can’t confirm those deaths,” he said.

The Observatory said 16 people, including three children, died in “intensive shelling” that targeted Baba Amro, with the Khaldiyeh and Karm al-Zaytoun districts also blasted.

Residents are reportedly trying to flee the Baba Amro neighborhood, where more troop reinforcements were deployed Tuesday. Activists say they fear a dramatic escalation of the assault, entering the 19th straight day.

Homs-based activist Abu Emad said there were still fears of an imminent ground attack against the Baba Amro area. He told The Daily Star: “More enforcements were on the road to Homs [Tuesday] ... There has been heavy shelling [Tuesday].”

Omar Shaker, another activist, told AFP the neighborhood had “no electricity, nor fuel,” and that “snipers have hit water tanks,” rendering the situation “bad beyond imagination.”

The Daily Star was not able to resolve the discrepancy in the death toll nor verify the reports of shelling.

Human Rights Watch said it had confirmed the use of Russian-made 240-mm mortars in Homs.

“It is by far the most powerful mortar in modern use – most other countries stop at 160-mm mortars, and a very powerful weapon,” HRW emergency director Peter Bouckaert told AFP.

“We have little doubt that those extremely powerful mortars are being fired by the regime forces into civilian neighborhoods of Homs. We are talking about a 250-pound mortar round that can only be fired from a heavy specialized armored vehicle and it requires a nine-person crew to operate,” he added.

The International Committee of the Red Cross called for a daily truce of two hours in Syria so it can deliver vital aid to afflicted areas, after saying a day earlier it was in talks with both sides to halt the violence.

The head of the rebel Free Syrian Army, Colonel Riyad al-Asaad, welcomed the call but voiced doubts that the “criminal” regime would commit.

The latest violence came as Russia, a key ally of President Bashar Assad, said it will boycott a conference in Tunis this week aimed at seeking political change in Syria.

China also refused to commit to attend the conference.

The Friends of Syria group will meet for the first time Friday after being created in response to a joint veto by China and Russia of a U.N. Security Council resolution condemning the crackdown that activist groups estimate has left 6,000 people dead.

The group is backed by members of the European Union as well as some Arab nations and the United States.

“China has received the relevant invitation,” Chinese Foreign Ministry spokesman Hong Lei told a regular briefing. “The Chinese side is currently researching the function, mechanism and other aspects of the meeting.”

And U.N. Secretary-General Ban Ki-moon said he was working urgently to find a special envoy for Syria who would initially have a humanitarian role but would also seek a political solution for the violence-torn country.

In the absence of that political solution, the U.S. seemed to give its strongest indication yet that it would consider arming opposition members.

In response to questions about aiding the Syrian opposition militarily, U.S. State Department spokeswoman Victoria Nuland told reporters the best outcome for Syria would be a political solution but if Assad refused this “we may have to consider additional measures.”

“We don’t believe that it makes sense to contribute now to the further militarization of Syria. What we don’t want to see is the spiral of violence increase. That said ... if we can’t get Assad to yield to the pressure that we are all bringing to bear, we may have to consider additional measures.”

The U.S. top military officer, General Martin Dempsey, said over the weekend it was “premature” to arm Syria’s opposition, but top Republican Senator John McCain called again for the outgunned rebels to be supplied with weapons Tuesday.

Damascus will hold a weekend referendum on a new constitution that could end nearly five decades of rule by Assad’s Baath party. Secular groups demonstrated outside the parliament in Damascus Tuesday against an article in the draft constitution that would require the president to be Muslim.