An 86-year-old woman who uses a walker was arrested in Philadelphia on Tuesday after pointing a gun at a bank teller and demanding $400, police said.

Sources told Philadelphia’s Fox 29 that Emily Coakley had been to the same bank a day earlier, but when she counted her money after returning home she believed she had been shortchanged by $400.

So on Tuesday afternoon she grabbed a gun and her walker and went back to collect, the sources said.

Police officers quickly moved in to make the arrest, Fox 29 reported. The elderly woman was then handcuffed and escorted out of the bank with her walker.

Coakley was charged with aggravated assault, robbery, terroristic threats and related offenses, according to police, and was released on her own recognizance.

“That's crazy. It's mind-blowing," one bank customer told Fox 29.

"That's pretty unusual. I never heard of a bank robber that age and armed," John McDonald said as he walked outside the bank.

Fox 29 reported that FBI agents examined the woman’s .38 caliber revolver and found that the gun was not loaded, but she was carrying bullets with her.