Pentagon says it is monitoring Chinese spy balloon spotted flying over US

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.