Foreign journalists perused the rows of corn and the groves of date palms pregnant with low-hanging fruit here this week, while agents of Syria’s ever present security services stood in the background, watching closely, almost nervously.

“You see — around us are farmers, corn, produce, nothing else,” said Ahmed Mehdi, the Deir ez Zor director of the Arab Center for the Studies of Arid Zones and Dry Lands, a government agricultural research center, as he led two of the journalists around the facilities.

It was here at this research center in this sleepy Bedouin city in eastern Syria that an Israeli journalist reported that Israel had conducted an air raid in early September.

On Monday, journalists toured the agricultural center at the government’s invitation to prove, Mr. Mehdi said, that no nuclear weapons program or Israeli attacks occurred there. “The allegations are completely groundless, and I don’t really understand where all this W.M.D. talk came from,” Mr. Mehdi said, referring to weapons of mass destruction.

“There was no raid here — we heard nothing,“ he added.

An entourage of the center’s employees lined up with him to greet the journalists. In a seemingly choreographed display, they nodded in agreement and offered their guests recently picked dates as tokens of hospitality.

President Bashar al-Assad, in a BBC interview, played down the Israeli raid, saying that Israeli jets took aim at empty military buildings, but he did not give a specific location. His statement differed from the initial Syrian claim that it had repulsed the air raid before an attack occurred.