A Syrian government spokesman called the raid "a crime and an act of aggression," claiming U.S. forces attacked a civilian building that was under construction. The building was about seven kilometers into Syrian territory, near the border post of Bu Kamel.
The U.S. military in Iraq says it does not have any information on the incident, and the U.S. government has not confirmed the attack nor commented on the allegations.
Sources at the local hospital say it had the bodies of seven men, all killed by gunfire.
Arab League Secretary General Amr Moussa condemned the attack.
He expressed sympathy and offered condolences to the families of those killed. He said Arab League officials in Cairo are following the situation in what he called a dangerous incident, which penetrated Syria's sovereignty.
The president of the Data and Strategic Studies Center in Damascus Imad Fawzi el Shueibi called the attack an "act of stupidity" by the parting Bush administration.
Press reports, quoting the mayor of the Iraqi village on the other side of the border, say Syrian Army troops took control of the area near the attack site.
Iraqi government spokesman Ali al-Dabbagh said this region is a theater of insurgent activities against Iraq, using Syria as a launch pad. He said Baghdad is asking Damascus to extradite members of an unnamed group it accused of killing 19 Iraqi security guards in a recent attack.
An Iraqi woman named Haifa Sabah al A'ani reacted on Jazeera TV's Web site, saying "What does Syria expect, if it lets terrorists into its country?"
A Lebanese man, named Sultan Khaled asserted, sarcastically, "Now the time has come for (Syrian President) Bashar al Assad to drink from the same cup as his Iraqi neighbors."