United Launch Alliance attempted to launch a U.S. national security mission with its Delta IV Heavy rocket at 2:04am early Saturday morning, but a questionable temperature reading on the rocket caused the countdown to be delayed until 3:28 a.m. from Space Launch Complex 37 at Cape Canaveral Air Force Station.

The countdown resumed and the launch was counted down to the expected words – liftoff, but with ignition flames billowing around the rocket the “heavy” rocket didn’t leave the ground due to an unexpected condition three seconds before liftoff, prompting an automatic abort, according to launch officials. It will take at least seven days to asses the issue and select a new launch date, according to ULA.

Inside the rocket’s nose cone was a spacecraft known as NROL-44, a payload for the National Reconnaissance Office.

It will take at least seven days to investigate the issue and select a new launch date, according to ULA.