"These despicable acts were committed by killers whose only faith is hate, and the United States will find the killers and they will learn the meaning of American justice."
"Anytime anybody attacks our homeland, or our citizens, we will be on the hunt. We will bring them to justice. Just ask the Taliban."
"This was a well-planned terrorist attack. It certainly has all the fingerprints of al-Qaida."
"Terrorism strikes everywhere and everyone. It is a threat to the civilised world."
"It is no consolation, but these things happen everywhere. It should increase our efforts and should make us not hesitate to take whatever measures that are needed to oppose these people, who know only hate, only killing."
"The prime minister strongly condemns this horrific attack and has expressed his sympathy for the families of all those who have been killed or injured.
If the aim is to kill Americans, Americans were killed and that is an outrage, but so were more people from different nationalities, among them Muslims and that's equally an outrage.
"What it underlines again is the need for international security co-operation at the same time as addressing those issues such as the Mideast peace process which these terrorists want to exploit."
"All the doors came in, the external doors, the internal doors, all the windows, and the next think I knew I was lying on my back in shattered glass."
"The fact we're seeing attacks on our homes, and particularly vicious attacks it just makes you wonder, where are you safe in the kingdom of Saudi Arabia?
"The fact they have attacked three compounds sends a message to the western community that we are not safe here. It's like they are saying, 'We can get you any time, anywhere.'"
"Our recent successes in Iraq, Afghanistan and in the global dismantling of terrorist cells may have understandably encouraged some Americans to turn their attention away from the war on terror toward other concerns. This attack is a reminder our enemies will not be similarly distracted. "
"This could be the beginning of a major campaign aimed at the Americans. This is the beginning of martyrdom operations."