Georgia's claims that Russian combat planes flew missions over its border this week were branded a "hallucination" by the chief of Russian General Staff Gen. Yury Baluyevsky on Thursday.

Baluyevsky's remarks came after Moscow received a note of protest from Georgia on Wednesday. "They claim they again saw, using their air defense facilities, a violation of their state border in the Kodori Gorge on Aug. 21," Baluyevsky was quoted by the Interfax news agency as saying.

"It looks like our Georgian colleagues are having an hallucination," he said.

Georgia has twice registered violations of its state border. The latest alleged intrusion by an aircraft from Russia into Georgian airspace occurred Tuesday near the village of Omarishara, in Upper Abkhazia (the upper part of the Kodori Gorge), the Georgian Foreign Ministry said in a statement Wednesday.

"The aircraft that ventured into Georgian airspace from Russia flew at an altitude of 4,000 meters at a speed of 470-490 km per hour and penetrated five km inside Georgian territory," the statement said.

But Baluyevsky countered, "I am a ground forces man, but I know that no combat plane flies at a speed like this."

Russian Air Force spokesman Alexander Drobyshevsky supported Baluyevsky's comments. Drobyshevsky was quoted by Itar-Tass as saying that "Russian Air Force planes on Aug. 21 carried out no flights along the Georgian border and there were no violations of Georgian airspace."

The Georgian Foreign Ministry, meanwhile, said it has "demanded prompt and clear explanations" from Russia.

"The violation of the airspace was recorded by both military and civilian radar," Georgian Deputy Defense Minister Batu Kutelia was quoted by Interfax as saying Wednesday.

He went on to say that the matter would have been "considered a simple violation" had it not been for the first incident on Aug. 6. As a result, it had now "gained particular importance," he said.

Georgian Interior Ministry spokesman Shota Ustiashvili said on Aug. 7 that two Russian fighter jets on the previous evening "violated Georgian airspace and dropped a rocket near the Tsitelubani settlement" which failed to explode and caused no casualties.

The village is located some 15 km from the Gori city and is close to the South Ossetia region.

But Russia has denied the attack. Moscow said none of its fighter jets were in the area, although its peacekeepers in South Ossetia did see an unknown plane fire a missile but they said it arrived from over Georgian territory.