Updated

Authorities are calling a Denver area bank robber the "Good Grammar Bandit" because his demand notes are perfectly typed, spelled and punctuated.

FBI officials on Monday said they believe the man robbed four banks in the Denver metro area in less than a week this month. Officials made a plea for the public's help in finding the man. In each case, he gave a teller a note that was typed and grammatically correct.

An FBI spokesman would not disclose how much money was taken during the robberies.

The agency described the man as about 6-feet tall, slender and in his 30s.

Surveillance photos from the robberies show him wearing a hooded sweatshirt, a cap and sunglasses.