Al Qaeda terrorists on Friday posted three photos on an Islamic Web site to prove they had beheaded Paul Johnson Jr, an American contractor they had abducted in Saudi Arabia.

The terrorists, who had abducted the 49 year old last week, had on Tuesday pledged to kill him in 72 hours unless Saudi authorities released Al Qaeda prisoners and Westerners left the country.

"As we promised, we the mujahedeen from the Falluja Squadron slaughtered the American hostage Paul Johnson after the deadline we gave to the Saudi tyrants," a statement said on the Web site. It has been translated from the Arabic.

"So he got his fair share from this life and for him to taste a bit of what the Muslims have been suffering from Apache helicopter attacks. They were tortured by its missiles."

Johnson, a Lockheed Martin Corp employee, helped maintain US-built Apache helicopters for the Saudi military. He had lived in the desert kingdom for more than a decade.

US Secretary of State Colin Powell condemned the killing, according to CNN. "It shows once again what the world is dealing with -- to behead somebody or murder somebody, somebody innocent who was only trying to help," he said.

"It will cause us and the Saudis to redouble our efforts to go after the terrorists wherever they are, wherever they hide."