(CNN) -- An unmanned cargo spacecraft failed to dock as scheduled Friday with the International Space Station, a NASA spokeswoman said.
The Progress cargo vessel, a resupply craft, was trying to dock with the space station when a technical problem occurred about 20 minutes before the scheduled docking time, said Lynette Madison, the spokeswoman.
The vessel flew about two miles past the space station.
"This is kind of a fluke event," she said. "We normally don't have any problems with Progress dockings. We dock those every few months. So this is an unusual event."
Six people aboard the space station -- three Americans and three Russians -- are not in danger, Madison said.
Engineers with the Russian Space Agency will try to dock the vehicle again, but they do not plan to try that on Friday, she said. They have "some" control of the vehicle, she said.
The craft launched Wednesday from the Baikonur Space Center in Kazakhstan, the state-run RIA-Novosti news agency of Russia said.
It planned to deliver "fuel, oxygen, scientific equipment and video and photo equipment" to the space station along with food, water and personal items for crew members, the news agency said.
Progress re-supply vehicles typically deliver supplies to the space station and haul away trash, burning up on re-entry.