A Palestinian protester burns an Israeli flag after the funeral of Palestinian Milad Said Ayyash who died of wounds sustained in yesterday's protests in east Jerusalem. -AP Photo

JERUSALEM: Masked Palestinians whirling slingshots clashed with Israeli riot police in two Arab neighborhoods of Jerusalem on Saturday after the shooting death of a teenage stone thrower.

It was a sign of rising tensions on the eve of Palestinian commemorations of their uprooting during Israel's 1948 creation.

The possibility of escalation comes at a critical time for US Mideast policy. President Barack Obama's envoy to the region, George Mitchell, resigned Friday, and the US president may now have to retool the administration's incremental approach to peacemaking. Obama is to deliver a Mideast policy speech in the coming week.

Mitchell held the job for more than two years, but had little to show for it.

Israeli-Palestinian talks resumed in September, but were quickly derailed by Israel's refusal to comply with an internationally mandated construction freeze in Jewish settlements in the West Bank and east Jerusalem, war-won territories Palestinians want for their state.