All flights of Russian airlines are carrying on without incident, the Russian aviation agency said in a statement.

There were reports earlier that five passenger planes sent out distress signals while flying over Russia. It was later reported that the signals were a result of a malfunction in the electronic aircraft tracking system.

"The Russian aviation agency denies media reports that on-board responders were engaged and some aircraft experienced emergencies. We emphasize that all flights are performed as usual and with the proper level of flight safety. Specialists of the St. Petersburg Regional Center of the Unified System of Air Traffic Management have not recorded any responders being engaged in emergency mode in the automated air traffic control system," the agency said.

According to the agency, media reports cited the foreign flight tracking service FlightRadar24, which appears to have had a glitch.

"Russian specialists are not responsible for the accuracy of the data provided by that service," the agency said.