The startling US commando attack inside Syrian territory over the weekend appears to amplify an emerging message to countries suspected of giving safe passage to terrorists: Take action, or else the US will.

A US military official in Washington says special forces conducted the raid in Syria on Sunday to target the network of Al-Qaida-linked foreign fighters moving through Syria to help fight in the war in Iraq. Syria said troops in four helicopters attacked a building and killed eight people, including four children.

"We are taking matters into our own hands," the US military official in Washington said, speaking on condition of anonymity due to the political sensitivity of raiding another country.