A former Marine, already irritated about the disappearance of $100 from his bank account, tackled a suspected robber who came into the bank wielding a fire extinguisher and demanding cash.

Timothy Armstead was waiting at the Washington Mutual Bank branch on Tuesday to discuss the missing money when the man came in and told bank employees he had a bomb. The man gave them five minutes to get $2,000 in $50 bills, DeKalb County police said.

As the employees went to the vault to comply, the unidentified man began loudly counting down the minutes, which attracted Armstead's attention, police spokesman Michael Payne said.

When the man then tried to walk out with the money, Armstead, 27, knocked him to the ground. He held the man down — lecturing him on his poor decision — until authorities arrived.

"I just told him it was a very stupid decision and now you get to spend 20 years of your life just for taking some money," Armstead told WSB-TV.

The man was taken to the DeKalb County Jail on suspicion of armed robbery. Jail officials declined to comment on his case Friday. A call to the DeKalb County Sheriff's office was not immediately returned.