The Chinese spy balloon that flew across the U.S. was able to gather intelligence from several sensitive American military sites, despite the Biden administration’s efforts to block it from doing so, according to two current senior U.S. officials and one former senior administration official.

China was able to control the balloon so it could make multiple passes over some of the sites (at times flying figure eight formations) and transmit the information it collected back to Beijing in real time, the three officials said. The intelligence China collected was mostly from electronic signals, which can be picked up from weapons systems or include communications from base personnel, rather than images, the officials said.

The three officials said China could have gathered much more intelligence from sensitive sites if not for the administration’s efforts to move around potential targets and obscure the balloon’s ability to pick up their electronic signals by stopping them from broadcasting or emitting signals.

The National Security Council referred NBC News to the Defense Department for comment. The Defense Department directed NBC News to comments from February in which senior officials said the balloon had “limited additive value” for intelligence collection by the Chinese government “over and above what [China] is likely able to collect through things like satellites in low earth orbit.”