TUALATIN, Ore. -- An anonymous tip led to the arrests of a woman and three men in a conspiracy to cause serious harm to the woman's ex-boyfriend, police said.

Tualatin officers arrested Olivia Jocelyn Bunn, 20, of Tualatin, on June 25 on charges of stalking and solicitation to commit burglary, assault and robbery after an anonymous tip informed them that she'd "ordered a hit" on her ex-boyfriend, police said.

The man who was going to be the target of the violence was also the father of Bunn's 2-month-old, police said. The source told officers that Bunn hired the three men to break into her ex-boyfriend's home and attack him, police said. Court documents also named another woman as a second victim in the case.

People close to the case said Bunn hired the hitmen because she was angry over her ex-boyfriend's relationship with another woman.

The three men -- Michael Asberry, 20, of Tualatin; Jeffrey Dahlke, 20, of Portland; and Sampson Johnson, 21, of Aloha -- were arrested on June 26 on charges of conspiracy to commit burglary, assault and robbery, police said.

Bunn was indicted on July 2 on charges of conspiracy to commit assault, conspiracy to commit robbery, conspiracy to commit burglary, soliciting assault, soliciting robbery, soliciting burglary, stalking and criminal mischief.

Bunn's mother said she doesn't know if her daughter is guilty but she is worried about the safety of Bunn's baby.

The three men were indicted on Tuesday on charges of conspiracy to commit assault, conspiracy to commit robbery and conspiracy to commit burglary.

Police: Woman Ordered Hit On Baby's Dad