The European Union is warning against a military escalation in Syria, even as it condemns the country for shooting down a Turkish military jet in international airspace last week.

EU foreign ministers appealed for calm after their meeting in Luxembourg Monday, a day before NATO ambassadors meet at Turkey's request to discuss what to do in response to the incident.

Turkey says its jet was on an unarmed training mission and inadvertently entered Syrian airspace for a brief period before leaving and being struck by Syrian fire several minutes later. Syria said it fired on the jet because it was flying close to its coast, in violation of Syrian airspace.

The Turkish Cabinet is meeting Monday about the incident, and Ankara has promised to take strong, decisive and legitimate action once the facts are known.

Meanwhile, EU officials approved a fresh round of sanctions on President Bashar al-Assad's government, adding a Syrian official as well as six companies and other entities to its sanctions list of more than 100 people.

The sanctions are in response to Mr. Assad's deadly crackdown on an opposition uprising.

Amateur video uploaded online shows what is said to be government shelling in various places across Syria Monday. The video includes a group of Syrian army tanks firing in unison.

Most of the video was purportedly shot in Homs province, including Homs City. Officials with the International Committee of the Red Cross say security concerns are keeping aid workers from evacuating hundreds of trapped civilians in Homs.

Separately, U.N. and diplomatic sources tell the Reuters news agency that a top U.N. human rights investigator is in Damascus for talks with senior Assad administration officials on opening a probe into massacres and other atrocities in the country.

If true, this would be the first time Brazilian expert Paulo Pinheiro has been granted permission to enter Syria since the U.N. Human Rights Council set up his team in September.