OLYMPIA, Wash. -- Thurston County authorities are investigating two strange Halloween robberies.

The Halloween heists were at Washington Mutual branches seven miles apart.

A wicked-looking bandit in a full witch's wardrobe walked in to the Washington Mutual branch in Lacey Monday afternoon, passed the teller a note demanding money and walked out with cash.

Video: 'Witch' Wanted In Halloween Holdups

"With it being Halloween, it's drawn your attention," said Sgt. Terence Brimmer of Lacey police.

As the woman ran east from the bank and across the street, the dye pack exploded and she dropped the money and her hat, which police recovered.

Then, just a half hour later, a Washington Mutual bank in Olympia was hit.

The costume was off, but police think it's likely the same woman.

Olympia and Lacey police are working on the cases together.

They think the woman may be responsible for four robberies in the last two weeks, including the heist at an Olympia Bank of America where she was caught on surveillance tape and a similar robbery at a West Coast Bank a few blocks away.

Despite the humorous costume, police detectives aren't laughing.

"Just to do something so bold tells us she's a dangerous person," Bremmer said.