Which poisonous gas is produced when coal is burnt without enough air supply?

Which poisonous gas is produced when coal is burnt without enough air supply?

جب کوئلہ کافی ہوا کی فراہمی کے بغیر جلایا جائے تو کون سی زہریلی گیس پیدا ہوتی ہے؟
Explanation

Carbon monoxide (CO) is a colorless, odorless, and tasteless gas that is produced when coal is burned without sufficient oxygen.

CO is highly toxic.

It can be deadly in high concentrations, as it displaces oxygen in the bloodstream.