Tanegashima, Japan ? Japan rocketed two spy satellites into space today from this remote island, giving it orbiting eyes to monitor North Korea’s missile and suspected nuclear weapons programs.

North Korea called the launch a “hostile act,” warning it might test-fire a missile in response.

The satellites, the first of at least four in the $2.05 billion spy program, were launched into clear but windy skies atop an H2-A rocket, the centerpiece launch vehicle of Japan’s space program.

“The rocket has successfully lifted off,” flight controllers announced minutes afterward. “It is flying smoothly and is on course.”

The satellites will allow Japan to monitor neighboring North Korea’s suspected development of nuclear weapons and to provide warning of long-range missile tests. Officials maintain they’re not intended as a provocation and will be used for other missions, such as monitoring natural disasters.

But they admit the program was prompted by the 1998 “Taepodong shock,” when a North Korean Taepodong ballistic missile flew over Japan’s main island before crashing into the Pacific off Alaska.

Japan's H-2A rocket lifts off from a launch pad at the Tanegashima Space Center. Today's launch of Japan's first spy satellite marked the start of a multibillion-dollar surveillance program prompted by tensions over neighboring North Korea's long-range missiles and suspected development of nuclear weapons.