The bus was immediately blocked and surrounded by the police.
The gunmen, who hijacked the bus early Wednesday, are demanding to be airlifted out of the country.
Three people, including the driver, a conductor and a woman passenger escaped moments after the first warning shots were fired by the hijackers.
Five hostages-- three women and two men -- were released about five hours later.
There are conflicting reports on whether the hijackers -- who are now reportedly demanding a fresh driver to take the bus to the airport, and a plane to take them to Russia -- are Russian or Albanian.
Five years ago, two buses were hijacked within two months by Albanian men, who were later shot dead by the police. A passenger was also killed in one of the incidents.