Editor's Note: After 19 months of incessant violence, the Syrian government has agreed to a cease-fire during the four-day Eid al-Adha holiday, which begins Friday, special envoy Lakhdar Brahimi said. He added that some rebels also "agreed to the principle" of a cease-fire.  But whether the words lead to any kind of peace remains uncertain. Here are the latest developments:

[Updated 1:52 p.m.] At least 124 people have been killed today in Syria, including 70 in Damascus and its suburbs, the opposition Local Coordination Committees of Syria said.

The opposition and the Syrian government are blaming each other for a massacre in the Damascus suburb Douma.  "At least one massacre is perpetrated almost every day across the country where many men, women and children are being slaughtered; all innocent civilians killed in their own homes and in cold blood," the LCC said.

Syria said earlier that "terrorists" carried out a "massacre" in the Damascus suburb of Douma today, killing 25 people, including three children.

Also, Syria is now saying a car bomb earlier today was in the Damascus neighborhood of al-Tadamun.  It killed four people and injured 11, Syria says on state-run media.

[Updated 11:26 a.m.] Syria says a car bomb exploded in the Damascus neighborhood of Daf al-Shouk, causing casualties. Officials didn't know how many people may have been hurt or killed.

[Updated 10:28 a.m.] Syria says "terrorists" carried out a "massacre" in the Damascus suburb of Douma today, killing 25 people, including three children.  The opposition Local Coordination Committees of Syria says 20 people were executed by Syrian forces in Douma.  It's not immediately clear if the two sides are describing the same incident.

In all, 80 people have been killed by Syrian forces today, the LCC says.

[Updated at 7:58 a.m.] The Free Syrian Army is ready to comply with a holiday ceasefire, but only if the Syrian military agrees to specific conditions, a spokesman told CNN from Aleppo, Syria.

"They need to stop the shelling on Homs, Idlib, Aleppo and every city," FSA spokesman Louai Miqdad told CNN. "The Assad military must pledge not to use drones to spy on our locations during the ceasefire and then unleash hellfire against our locations when the four days are over."

Miqdad said there were concerns about the real reason the Syrian government was agreeing to a ceasefire.

"The Assad regime wants to buy time so they can reorganize their troops and send reinforcements, taking advantage of the truce then attack with full force," Miqdad said. "We are not willing to give the regime forces a break so they can come back with more reinforcements and break our backs. We accomplished so much in the last few weeks and we are not willing to sacrifice ourselves by being the scapegoat, the weaker link who will be wiped out after a 4 days ceasefire ends."

[Updated at 6:34 a.m.] Any promise of a cease-fire is just a stalling tactic on the Syrian government's part, the opposition Syrian National Council said.

“Based on our long experience in dealing with the Assad barbaric regime, we know that the Syrian government is just buying time and playing on words," the group's spokesman George Sabra said in a phone call from Paris. "The whole world knows that the Syrian regime cannot be trusted and doesn’t have any credibility in fulfilling any promise that they make to anyone."

[Updated at 6 a.m.]In an email sent from the Syrian foreign affairs ministry, Jihad Makdissi said: “The issue of halt of the military operations during the Eid al-Adha holiday is still under study by the General Command of the Military and the armed forces. A final decision will be issued tomorrow in this regard”.

[Posted at 5:41 a.m.] U.N special envoy to Syria Lakhdar Brahimi said the Syrian government has agreed to a ceasefire during the Eid al-Adha holiday, adding that some opposition armed groups that he had been able to contact had “agreed to the principle” of a ceasefire.

The Muslim holiday of Eid al-Adha begins Friday.

Brahimi was speaking at a press conference in Cairo, after a recent visit to Damascus.