Syrian protesters turned out in force to greet Arab monitors in one flashpoint town in the early days of their mission. But the observers never showed up, one activist said. Instead, security forces fired on the crowd.
Arab foreign ministers meet on Sunday to decide the future of the observers, whose month-long mandate expired on Thursday.
The young activist, who gave his name as Manhal, said his town in the northwestern Idlib province had wanted to show the monitors, sent to see if an Arab peace plan was working, how determined they were to topple President Bashar al-Assad.
"I was amazed at how many more people went to the streets. It was like the revolution was starting again, people want to show we are not just YouTube videos, we really exist," he said.
"But the price was high. I feel bad people didn't realise the bloodshed won't stop," he told Reuters by telephone. His story, like many others, is hard to verify due to the government's tight media restrictions.
Protesters like Manhal say they are conflicted about the value of an Arab mission that cast a spotlight on their 10-month-old movement but failed to offer a reprieve from bloodshed that may be pushing Syria towards civil war.
The British-based rights and advocacy group Avaaz lists at least 20 instances of security forces opening fire on protesters before, during or after a visit from the Arab monitors.
On the last day of their mission, monitors drove into the cramped alleyways of a rebel-controlled neighbourhood in the city of Hama, greeted by crowds shouting "freedom".
Video posted by activists showed fighters in green military fatigues riding on the roof of the monitors' vehicle and clinging to its doors, their rifles slung across their backs.
Violence that initially dropped when the mission began has spiked, raising the toll to its average level in recent months.
According to the Syrian Observatory for Human Rights, 454 civilians and 146 soldiers, including 27 deserters, have been killed since the monitors deployed on Dec. 26.
Avaaz says 746 civilians were killed in the past month, including 80 people who died in three bombings in Damascus.
The monitors were checking Syria's compliance with an Arab plan that called for an end to killings, an army withdrawal from the streets, release of detainees and a political dialogue.
Critics of the 165-strong mission say it has only bought more time for Assad to pursue a violent crackdown.
"Their presence gave legitimacy to the regime, in its mind, to continue its suppression ... The mission should be seen as a failure," said Chris Phillips, a Middle East specialist at the University of London. "What more do the monitors need to see?"
On one occasion, a video posted by activists showed orange-vested monitors ducking behind walls in Homs as gunfire erupted. It was not clear if they were the target or who was shooting.
In another incident, pro-Assad demonstrators in the port of Latakia swarmed cars carrying monitors and punched them.
At least one monitor quit in disgust, saying the mission was a "farce".
Activists say the authorities have tried to deceive the monitors by hiding or repainting armoured vehicles and staging partial prisoner releases that left thousands more behind bars.
The mission depended on the authorities for transport and security, compromising its independence in the eyes of critics.
Nevertheless, some opposition figures believe the monitors have played a positive role, even if their small numbers meant it was hard for them to track events in a country of 23 million.
"They encouraged people to join peaceful protests and showed you don't need to resort to violence to make your voice heard," said Louay Hussein, a moderate opposition politician.
Some activists said they had contacted the observers over the Internet to evade eavesdropping by Syrian secret police.
"I talk to monitors on Skype every day and I know most are sympathetic, but sympathy hasn't done us any good. The regime is still killing us," said Damascus-based activist Mar Ram. "They have let us down, big time."
Activists like him fear that frustration with the failure of the Arab League or world powers to rein in Assad may encourage more Syrians to join an insurgency now overshadowing what began in March as a peaceful protest movement inspired by Arab uprisings across the region.
"I'm worried people will feel compelled to turn to violence," said an activist who gave his name as Hamad, in the Damascus suburb of Douma, where anti-Assad sentiment runs high.
"A lot of Syrians are unemployed or uneducated and have felt marginalised for so long. They are impatient and the monitors seem useless and helpless. It doesn't inspire people to stick to peaceful means," he said.
During the monitoring mission, the mountain town of Zabadani emerged as a new centre of armed uprising, where rebels forced the military to retreat under a truce on Wednesday.
"We tried peaceful protests. We saw our wives and sons killed. The Arab delegation barely visited us. We had to defend ourselves," said a young man named Ahmed, who told Reuters by Skype that he had joined army deserters in Zabadani.
"The choice is victory or death. This is a martyrdom operation now."