Washington, Feb 3 : The Pentagon has detected and is tracking a high altitude surveillance balloon that is over the continental US right now. The Pentagon has been tracking the balloon for several days as it made its way over the northern US, media reports quoted Pentagon Press Secretary Brig. Gen. Pat Ryder as saying. The US government is "confident" that the surveillance balloon belongs to China, Fox news reported, citing a senior defence official. Officials were considering bringing the balloon down with military assets, but decided against doing so because of the risks associated, he added. The balloon is currently travelling at an altitude well above commercial air traffic and does not present a military or physical threat to people on the ground. "Instances of this kind of balloon activity have been observed previously over the past several years. Once the balloon was detected, the US government acted immediately to protect against the collection of sensitive information," Ryder said during a briefing on Thursday afternoon. /IANS