Russia will carry out two unmanned test launches of Soyuz carrier rockets in the coming fall before using them to deliver crews to the International Space Station, a source in the Russian space industry said on Friday. One of the Soyuz rockets will be used to deliver a new Progress M-13M space freighter to the ISS, the source said. Wednesday's accident involving a Soyuz rocket, when a Progress M-12M space freighter was lost because of a rocket engine failure, raised questions about Russia's ability to fulfill its obligations in delivering crews to and from the ISS. A high-ranking source in the Russian space industry, as well as NASA officials, suggested that the next mission to the ISS due in September was likely to be delayed because of the accident. After the retirement of the U.S. shuttle fleet earlier this summer, Russian Soyuz spacecraft became the only way for astronauts to reach the ISS until at least the middle of the decade. NASA is paying its Russian counterpart Roscosmos more than $1 billion for crew transport services over the next four years. The accident, the second spacecraft loss for the Russian space industry in within a week, prompted an order by Russian Prime Minister Vladimir Putin to review and improve control procedures in the space industry. Russian space agency Roscosmos said it would set up a special commission for this purpose.