In newly filed court documents obtained by 12 News, Phoenix police lay out their case against .

The 38-year-old Marrufo, a level two registered sex offender, is accused of exposing himself and masturbating in front of as many as 10 victims including two 6-year-old girls.

Chave, who lives in a neighborhood near 55th Avenue and Thomas Road, says her 9-year-old sister walks the same route to school as one of the alleged victims.

“She was hearing about a guy going around showing little girls his privates,” said Monserit Chavez.

“We were nervous for her,” Chavez told 12 News. “My mom would walk her to school now.”

Last week, investigators say Marrufo masturbated in front of two 13-year-old girls as they walked to school near 35th Avenue and Roosevelt Street.

The teens got his license plate, which police say led them to a white Dodge Caravan owned by Marrufo.

When 12 News went by Marrufo’s home off 67th Avenue, the van was still parked in the driveway.

Police say it's now linked to a series of flashings in various areas of west Phoenix.

According to court documents, the crimes all have similar MO’s.

The suspect would allegedly drive up to a young girl, gets her attention then try and get her to look into his vehicle where his penis would be exposed and in several cases the suspect was said to be masturbating.

Police say the victims told detectives Marrufo would offer them a ride or in one case allegedly told a 10-year-old girl who was walking alone that, "he wanted to show her something."

"Thank god they got him,” said Chavez. “Thank god it wasn't my little sister.”

Court documents also show several victims picked Marrufo out of a photo lineup.

Marrufo’s previous arrests include sexual abuse and sexual assault.

He denies these latest allegations, saying he never exposed himself to any of the victims.

In court documents, he reportedly told police that he was involved in three separate incidents but that he only yelled at the girls and gave them the finger.