Syrian security forces have killed at least two people at funeral services for a prominent Kurdish opposition leader – a gathering that turned into a mass rally against President Bashar al-Assad.

Activists say the incident took place on Saturday in the northern town of Qamishli, where about 50,000 people had gathered to pay their last respects to Mashaal Tammo.

He was a founding member of the Kurdish Future Party and a member of the newly formed opposition Syrian National Council.

Witnesses say mourners called on Mr. Assad's government to step down, chanting “leave, leave.”

Tammo was killed by masked gunmen who stormed into his home on Friday. State-run media reported the attack, saying the opposition leader was gunned down by “armed terrorists.”

World powers condemned Tammo's assassination. The United States blamed the Syrian government for the attack and said “President Assad must step down now before taking his country further down this very dangerous path.”

A Swedish development group, the Olof Palme International Center, says Syrian National Council leaders are meeting in Stockholm on Saturday to discuss ways to promote democracy and human rights in Damascus.