Some 400 US Dutch NATO troops deployed on Turkey's Syrian border to operate Patriot missile 0712123.

"Nobody knows what such a regime is capable of and that is why we are acting protectively here," German Foreign Minister Guido Westerwelle said of NATO's move.

U.S. Defense Secretary Leon Panetta said Thursday the latest intelligence reports heightened fears Assad would use chemical weapons on the rebels trying to oust him.

"The intelligence that we have raises serious concerns that this is being considered," he said.

Over four decades, Syria has amassed one of the largest undeclared stockpiles of chemicals in the world, including huge supplies of mustard gas, sarin nerve agent and cyanide, the CIA says.

Syria denounced the NATO action and the U.S. and German statements.

Syrian Deputy Foreign Minister Faisal Miqdad told pro-Assad Lebanese satellite TV station al-Manar, affiliated with the Shiite militant group Hezbollah: "Syria stresses again, for the 10th, the 100th time, that if we had such [chemical] weapons, they would not be used against its people. We would not commit suicide."

The opposition Local Coordination Committees of Syria said at least 89 people were killed in Syria Thursday. It said Syrian troops shelled at least 248 points, with 13 points shelled by warplanes, mostly in the Damascus suburbs.

Two points were hit with cluster bombs and four with barrel bombs, the group said.

Cluster bombs are air-dropped or ground-launched and release or eject smaller sub-munitions, or explosive "bomblets." Barrel bombs are large oil drums packed with TNT, oil and chunks of steel and dropped from helicopters. These improvised weapons are intended to cause maximum death and destruction, British newspaper The Daily Telegraph reported.