An unknown assailant stabbed a McDonald's employee to death early Sunday during an attempted robbery at the fast food chain's outlet in northern Jordan, a security official said.

A preliminary investigation showed that the woman, Suhad Atawneh, 27, was stabbed to death when the thief was surprised by her presence in the restaurant, the official told The Associated Press on condition of anonymity because he was not allowed to speak to the media.

"There is no terror motive and all indications point to an attempted robbery," the official added.

A McDonald's spokeswoman in Jordan confirmed the murder, but declined to provide further details and spoke on condition of anonymity, citing the ongoing investigation.

An eyewitness, who spoke on condition of anonymity for fear of retribution, said the victim was found lying on the floor of the restaurant early Sunday. He said several stab wounds were visible on her body.

The killing took place in Irbid, 90 kilometers (55 miles) north of the Jordanian capital.

McDonald's has one branch in Irbid.

The killing comes amid Al Qaeda threats against U.S. interests in the Mideast. The terror network has pledged to avenge the killing of Jordanian-born militant Abu-Musab al-Zarqawi, who died after a U.S. airstrike in Iraq 10 days ago.

Last week, the U.S. State Department warned Americans living in the Middle East or traveling there about "ongoing security concerns in the region in light of recent events, including the death of Abu Musab al-Zarqawi."

"U.S. citizens are reminded to maintain a high level of vigilance and to take appropriate steps to increase their security awareness," the statement said.

It said "credible information has indicated terrorist groups seek to continue attacks against U.S. interests" in the region and in North Africa.