Officials say balloon has been watched for a few days but has decided not to shoot it down for safety reasons
The Pentagon has said it is tracking a Chinese spy balloon flying over the United States but had decided against shooting it down for safety reasons.
Defence officials said the balloon has been watched for a couple days since it entered US airspace, flying at high altitude. It has been monitored by several methods including manned aircraft, and has most recently been tracked crossing over Montana, where the US has some of its silo-based nuclear missiles. As a precaution, flights out of Billings Logan airport were suspended on Wednesday.