Three schools in the David Douglas School District, which covers East Portland, found racist graffiti marring the walls of their buildings Monday morning.

Between 11 p.m. and 3:20 a.m., two men traveled between Ventura Park Elementary, Lincoln Park Elementary, and Mill Park Elementary, and left behind messages including "Hail Hitler," "666," and several racial slurs.

According to an email to school board members sent by Superintendent Ken Richardson, the school district reviewed video surveillance footage that suggests the same two men vandalized all three schools—and they may be the same men who attacked Menlo Park Elementary School last week.

At Menlo Park Elementary, the vandals also threw eggs and set a porta-potty on fire.

Ana del Rocio, a member of the David Douglas school board, tells WW she was horrified when she found out about the most recent racially-charged vandalism.

"Whereas last week I felt like it was really tragic act of violence, now we know this is a concerted effort that is targeting children of color," she says. "It's so heinous to target children—it's so heinous that I don't know if we can wait for a political solution. I want to talk community defense."

Del Rocio says she's frustrated because the police have not yet arrested the men behind the hateful messages.

School officials emailed photographs of the graffiti to the Portland police school resource officer responsible for the district on Monday, but the official police report was not filed by school officials until Tuesday morning. Portland police spokesman Chris Burley says the investigation is ongoing.

Unite Oregon and the David Douglas School Board organized a community meeting and vigil to discuss the four vandalism incidents with parents and students.

State Rep. Diego Hernandez (D-Portland) said in a statement that he will be attending the community meeting.

"Schools are meant to be safe places for our students to learn and feel welcomed," he said in a statement on the incident. "This is an appalling and offensive display of ignorance and we should all stand together in denouncing racism and hate."