Nine Russian navigation satellites had gone out of service for the second time in this month, the Federal Space Agency Roscosmos said Tuesday.

According to Roscosmos, between 01:00 and 01:30 Moscow time (2100 - 2130 GMT), eight satellites of the Glonass navigation system reported malfunctions. Earlier, at 22:20 Moscow time (1820 GMT) on Monday, one more Glonass satellite reported a glitch.

Roscosmos said eight out of nine satellites have already been recovered.

"The half-hour glitch was fixed," the Itar-Tass news agency quoted Nikolai Testoyedov, director general of the Reshetnev Information Satellite Systems Company, which produces the satellites, as saying.

He blamed the malfunctions to human factor -- wrong data entry to the satellites' onboard computers happening in a process of software updating.

That was the second time in two weeks when Glonass system reported malfunctions. On April 2, it failed for over 10 hours with all its satellites sending wrong navigation data to the users.

The Russian global navigation system Glonass currently consists of 23 satellites.