Iran’s Islamic Revolutionary Guard Corps (IRGC) said Wednesday it launched the nation’s first military satellite into orbit, a surprise development that provides a peek into the country’s secretive space program.

The launch, announced by the IRGC’s news service, comes amid heightened tensions with the U.S. and raised concerns over whether the technology used to send off the satellite could also be employed to develop intercontinental ballistic missiles.

“The successful launch of this satellite has promoted new dimensions of the defense power of the Islamic Republic of Iran,” said Maj. Gen. Hossein Salami, the IRGC’s commander. “This action will be a great success and a new development in the field of space for Islamic Iran.”

The IRGC said the satellite, dubbed the Nour, meaning “light” in Farsi, was launched from the Markazi desert and orbited Earth at 264 miles.

Wednesday’s launch follows several failures by Iran to put a satellite into orbit. The last attempt was in February, when the IRGC tried to put its Zafar 1 communications satellite into orbit.

The IRGC, which operates its own military apparatus parallel to Iran’s regular military, is known to tout hard-line stances and is loyal solely to Supreme Leader Ayatollah Ali Khamenei. However, Iranian Information and Communications Technology Minister Mohammad Javad Azari Jahromi told The Associated Press that the Guard’s space program was “defensive” in nature and that the overall program was “peaceful.” 

The State Department dismissed Iran’s claims that its program is peaceful, saying the launch violates a United Nations Security Council resolution barring it from any activities related to ballistic missiles.

“We have seen reports of Iran’s announcement that it launched a military satellite into space. Iran has long pretended its space program is peaceful in nature,” said a State Department spokesperson. “Iran’s development of Space Launch Vehicles poses a significant proliferation concern. This vehicle incorporates technologies identical to, and interchangeable with, ballistic missiles, including longer-range systems such as intercontinental ballistic missiles.

“We will continue to use all the tools at our disposal to prevent Iran’s further advancement of its missile program, particularly efforts to refine or develop such technology through its launches of satellites.”

The launch comes as tensions spike between Washington and Tehran on a number of fronts. 

President Trump unilaterally withdrew the U.S. from the landmark nuclear deal with Iran in 2018, setting off worries that Tehran would develop nuclear weapons and long-range missiles. Iran later officially declared it would shirk its obligations under the pact. 

The two nations were brought to the brink of war earlier this year when the U.S. assassinated Gen. Qassem Soleimani, the commander of the IRGC’s Quds Force who was a revered figure in Iran but was blamed by the Pentagon for the deaths of hundreds of Americans. Iran has since had its proxies fire rockets at military bases housing U.S. forces in Iraq and deployed ships to harass U.S. vessels in international waters, drawing a warning from Trump on Wednesday that he would order the U.S. Navy to “shoot down and destroy any and all Iranian gunboats if they harass our ships at sea.”

Updated at 2:37 p.m.