The attack came on the day when pro-democracy activists held a “day of anger” against Russia for its support to Bashar Assad’s regime.

The five were shot dead by security police snipers from the rooftop of a public school and a municipal water tank in the town of Kfar Nubouzeh, when hundreds of mourners began chanting slogans demanding the downfall of Assad, activists in contact with residents said.

Demonstrators burned Russian flags in the flash point protest hubs of Homs in the center and Daraa in the south in protest at Moscow’s support for Assad, activists said.

“Do not support the killers,” activists urged Russia in a message announcing Tuesday’s action posted on The Syrian Revolution 2011, a Facebook page that has been a driving force behind the protest movement.

“We express our anger toward Russia and the Russian government. The regime will disappear but the people will live,” the activists added.

Moscow has blocked Western-led efforts at the UN Security Council to impose sanctions against the Syrian regime and is promoting a rival draft resolution that simply calls on the government and the opposition to open direct talks.

On Tuesday, police and troops again deployed in force, carrying out search and arrest operations in a string of towns, activists said.

One person was killed during searches in Deir Ezzor province in the northeast while five more were wounded when troops went house to house in Houla in Homs province, the Syrian Observatory for Human Rights said in Cyprus. The security forces arrested more than 160 people in Idlib province near the Turkish border, and dozens more in Daraa, in satellite towns around the capital, and in the Mediterranean coastal towns of Latakia and Banias, the Britain-based watchdog said.

Meanwhile, Syrian authorities detained a prominent psychoanalyst as she was preparing to board a flight to Paris from Damascus, her husband said in a statement seen Tuesday. Rafa Nached was arrested by officers in Syria’s air force intelligence service on Saturday as her luggage was being scanned at Damascus airport, said Faisal Mohammed Abdullah, professor of ancient history at Damascus University.

“She is suffering from several diseases and she was heading to Paris for family and health reasons,” Abdullah said of his 66-year-old partner.

Nached was one of the organizers of weekly meetings for Syrians of all backgrounds and political affiliations to discuss their concerns in the face of a deadly crackdown by the security forces.