An 11-year-old girl is among the victims.
The alarming pattern of behavior started on Monday, police say, at the corner of Osborn Street and Pitkin Avenue in Brownsville. A teenage girl was approached by a man asking her to take a photo. He claimed he forgot his camera and led her into a nearby apartment building.
"It's not surprising. I'm just hoping that the school is going to teach our children what to do in case these things happen," Brownsville parent Latoya Harris told CBS2's Kevin Rincon.
That is the plan at Prep Ocean Hill Middle Academy. That's because on Wednesday, it happened again right outside their doors along Christopher Avenue.
While the victim isn't a student, the school sent a letter home to parents that says in part: "We understand that this is a scary situation for our school community ... We encourage our scholars, our families, and our staff to remain aware of their surroundings."
"That is disgusting. That's horrible and I'm so sad that has happened. I can't even imagine what the parents feel like," another Brownsville parent said.
In each of these instances, police say the suspect used his dogs to lure the girls off the streets and into a building. In at least one case, cops say a 13-year-old was groped.
Investigators say the other two victims were 11-12 years old. The suspect targeted these girls in the morning before the start of school, and all three incidents happened within blocks of each other.
"Molesting young kids, that's not nice. That's scary," one Brownsville resident said.
"Obviously that's crazy. Obviously a pedophile or whatever. That's pretty bad," another person said.
"We got demons out here," another man said.
In the Brownsville community, families are doing what they can to keep their kids safe.
"As parents and as a school, we just have to teach our children to do exactly what they did -- let somebody know. That way it's brought to attention," Harris said.
For now, police are actively searching for the suspect. They've also increased patrols in the area as a precaution.
CBS2's Kevin Rincon contributed to this report.
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