Syria is facing increased pressure from world powers to end its crackdown on dissent, but activists say violence in the country continues to escalate.

An activist with the Syrian Observatory for Human Rights told VOA on Tuesday that Syrian forces have publicly executed 22 activists in a Damascus suburb and arrested about 600 people. The opposition group says the suburb had been under siege since Sunday, when forces backed by tanks pushed into the region.

Meanwhile, the U.S. and Germany say the U.N. Security Council must respond to Syria's crackdown on anti-government protesters after U.N. investigators detailed grave rights abuses they say were ordered by the “highest levels” of President Bashar al-Assad's government.

On Monday, a U.N. commission investigating allegations of human rights violations in Syria accused government troops of “summary execution, arbitrary arrest, enforced disappearance, torture, sexual violence, as well as violations of children's rights.”

The report said Syrian forces have killed 256 children and that “torture was applied equally to adults and children.” The group's findings will now go to the Human Rights Council and the U.N. General Assembly, which will decide what to do next.

Turkey said Tuesday that it may shift its Middle East trade routes to go through Iraq — cutting out Syria as a transit country if unrest there worsens and embargoes against Damascus go into effect.

Turkey and Syria abolished visa requirements in 2009 and had planned to raise their trade volume.

Also, the EU says it plans to impose additional sanctions on Mr. Assad's embattled government. EU foreign ministers will vote Thursday on proposals to further restrict trade and economic dealings with Damascus.

The United Nations says more than 3,500 people have been killed since March in connection with the uprising.