Story highlights Police plan to canvas L.A.'s Hispanic neighborhoods Thursday

From 1996 to 2005, the 'teardrop rapist" attacked more than two dozen women

The case went cold until six months ago, Los Angeles police say

The suspect's moniker comes from reports of a teardrop tattoo on his face

Police say he strikes in the early morning hours, often before the sun comes up, and his method is usually the same. While on foot, he approaches his female victims, many of them minors, as they walk alone to school or wait at a bus stop, and he strikes up a casual conversation with them.

Then he quickly brandishes a knife or gun and forces his victims to a secluded nearby area, where he sexually assaults them. And just like that he is gone. But he leaves behind his DNA and -- for his victims -- the memory of a teardrop tattoo on his face.

Dubbed the "teardrop rapist," the man is one of Los Angeles' most prolific criminals. Since 1996, police believe the same man assaulted girls and women 35 times throughout a broad swath of the city center. Then in 2005, he stopped.

For seven years, the case went cold until November when, according to recent DNA tests, the man attacked again. Now, just seven months later, he has struck yet again making his capture a top priority for the Los Angeles Police Department, which has launched a massive manhunt to end the assaults.

Police Deputy Chief Kirk Albanese has this warning for residents citywide: "For families that have teenage daughters walking we have had several occurrences where the victim has been as young as 14, 15 years old. We are asking parents to ensure that their young teenage daughters are accompanied."

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The attack that put this cold case back in the spotlight occurred at 5:30 a.m. in the morning hours last November when a 15-year-old Latina was walking in a residential neighborhood. The suspect approached the victim by asking for directions, then pulled out a gun and forced her into a yard, where he sexually assaulted her. At the time, it was initially investigated as another sexual assault case. Then, a couple of months later, the DNA results matched 10 other sexual assaults that police have linked to the same man, known as the "teardrop rapist."

After investigating some leads, police decided last month to go public with the DNA findings that showed the "teardrop rapist" had struck again after an apparent six-year hiatus. Now, a task force of 20 police detectives is following new leads and resurrecting any clues from previous cases dating back to 1996.

The latest assault attempt in the case was June 15, police said. Authorities plan to canvas Hispanic neighborhoods on Thursday.

The suspect has been described as a Hispanic male, 40 to 55 years old, with brown eyes and brown hair. His height ranges between 5 feet 2 inches and 5 feet 6 inches tall, and his weight is believed to be 130 to 170 pounds. He has possible teardrop tattoos below one of his eyes and has been seen wearing a dark-hooded sweatshirt as well as a baseball cap or a dark-colored beanie on his head.

Despite victims' conflicting descriptions, police believe one man is responsible for 35 sexual assaults.

Detective Jesse Alvarado, who is leading the task force with fellow detective Sharlene Johnson, said the suspect often goes unnoticed in the neighborhoods where he has targeted his victims.

"He can walk up to somebody and spark up a conversation, and the victim doesn't feel threatened until the weapon is seen," Alvarado said. "So he blends in, and nobody is saying, 'What is this guy doing in our neighborhood?' "

The pattern of attacks shows the suspect never strikes in the same place twice, Alvarado said.

"He's just all over the place, and he appears to be familiar with the area -- whether he lives in the area, has family (there) or works in the area."

DNA evidence has linked 11 of the 35 victims, who range in age from 14 to 41. The remaining 24 cases are tied together by the similarities in the attacks and descriptions of the suspect. The locations of the attacks are spread out in a wide area concentrated through the center of Los Angeles.

Inside Los Angeles police headquarters, the Special Assault Section resembles a command center for an emergency operation. On a wall there are poster boards with the latest leads written on them. Detectives are busy combing through some 700 boxes of old and closed cases, visiting old locations and even re-interviewing victims to shake out any possible clues.

Johnson insists the task force will leave no stone unturned.

"We have decided to completely re-investigate it from the beginning, going through all of the original cases, all of the original follow-up investigations that were done," she said.

The detectives have already uncovered a previous composite sketches by going through some old cases. All 11 sketches depict the teardrop rapist through the years, but some are very dissimilar: In some sketches, he has a teardrop tattoo on the left side of his face, while it's on the right side in others; some sketches have two teardrops, and others have none at all.

Police admit the wide variation of composite sketches can be confusing but said at this point they cannot narrow a sketch down to just one. The detectives stressed the sketches are simply a guide and another tool to help make the community aware, with the hope that they might lead to someone recognizing the suspect.

Johnson said these attacks "happen very quickly," explaining the different descriptions of a suspect who police believe is the same man.

"There is a knife involved, there is a gun involved; every person focuses on something different," she said.

Despite the massive police investigation, Alvarado said he believes ordinary citizens will help crack the case.

"It's gonna be that one little thing where someone says, 'It looks like that guy I used to work with,' " Alvarado said.

To get the public's attention, Los Angeles police are sending out community alerts with a description and composite sketches of the suspect, and the city has offered a $50,000 reward for information leading to an arrest.

Johnson said she won't be able to rest until police get their man.

"We will figure out who this is; we will arrest him, and we will make sure he gets prosecuted, and we will do the best that we can to make sure he doesn't victimize any women again."

For Alvarado, the case hits close to home.

"I'm a parent, I have a daughter; my thing is it's happened here, and it could happen where I live," he said. "So our job is to find this individual no matter what it takes."