(AP) -- Technicians at a space center in Kazakhstan have hoisted a rocket onto its launch pad ahead of Friday's blastoff of a NASA astronaut and two Russian cosmonauts to the International Space Station.

NASA's Tracy Caldwell Dyson and Russians Alexander Skvortsov and Mikhail Kornienko are to blast off at 10:04 a.m. (0404 GMT) Friday for their six-month mission in the orbiting science lab.

Workers at the craft's storage hangar slid open the gate just before daybreak Wednesday and mounted the Soyuz rocket on a flatbed train for slow transit to the launch site.

Armed police with sniffer dogs walked ahead of the train and a helicopter circled overhead amid heightened security following the Moscow subway bombings, which killed dozens of people.