WORCESTER, Mass. — Monday is the 34th anniversary of the Isabella Stewart Gardner Museum heist in Boston, which some say was inspired by a theft nearly 20 years earlier at the Worcester Art Museum. 

The director of security and chief investigator at the Isabella Stewart Gardner Museum said the Worcester heist was the first time a museum was robbed at gunpoint and back then was considered the biggest art heist.

Anthony Amore said the mastermind behind the theft, Al Monday, made other members of a gang rob the art museum in broad daylight.

They stole four paintings and shot a guard on their way out.

The paintings were recovered shortly after.

"People were pretty much aware of who was behind the heist,” said Amore. “They were recovered by a couple of guys that were awaiting sentencing from a judge in Worcester, decided if they could recover the paintings they would be able to carry some favor with that judge and the sentencing, so they put a gun in Al Monday’s stomach and said, 'take us to them,' and he did. And the paintings were recovered."

Meanwhile, the Isabella Stewart Gardner Museum heist investigation continues to this day.

Amore said since the pieces stolen are so valuable and recognizable, it's believed the thieves never tried to sell them.