Explosions and machine gun fire have rocked the Syrian town of Rastan after security forces with tanks pushed into the region on Tuesday in a crackdown on dissent.

Rights activists say at least 20 people were wounded after forces entered the town, which is between the flashpoint cities of Homs and Hama.

The region has been a central point in the protests against Syrian President Bashar al-Assad.

The operation comes a day after Syrian Foreign Minister Walid Mouallem blamed armed groups for the situation in Syria, and lashed out at the United States and European Union for imposing sanctions.

In a speech Monday to the U.N. General Assembly in New York, Mouallem accused the U.S. and EU of jeopardizing the interests and basic needs of Syrians while pronouncing concerns for their security and rights.

Human Rights Watch rejected Syria's explanation of the violence. The group's U.N. director said facts documented by the U.N. and Human Rights Watch show the Syrian government has carried out a “merciless campaign” of killings, torture and arbitrary detentions of its people. He urged the U.N. Security Council to take action.

German Foreign Minister Guido Westerwelle also called for Security Council action, while Chinese Foreign Minister Yang Jiechi urged on all sides in Syria to show restraint.

President Assad has repeatedly sent troops across the country to quell anti-government protests.

The U.N. says the government crackdown has killed at least 2,700 people since mass protests started in March.