NEW YORK (CBSNewYork) — Monday was day 11 in the search for Lauren Spierer, the young Westchester County woman who vanished while away at Indiana University.

Spierer’s mother made an emotional message to anyone who may have taken her daughter.

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“To say to the person that has Lauren or has harmed Lauren, shame on you, shame on you,” emotionally drained and physically exhausted Charlene Spierer said, addressing whomever may have been involved with her daughter’s disappearance.

Spierer also spoke directly to Lauren.

“Don’t take my appearance of despair to mean that I’m not as strong as ever, I’m not as determined as ever. I’m here for you 100 percent. I will never leave you,” she said.

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Police in Bloomington, Ind., said they have 10 persons of interest, including Lauren’s boyfriend, Jesse Wolf, and one of the last people she was seen with, Corey Rossman.

Investigators have also found Lauren’s keys on the railing of an apartment building, near where she was last spotted. They said they have been poring over surveillance video from that building.

“We’re going to maintain custody of that video and not release anything or specific details about it, and I understand you want to get to the nuts and bolts of it. We’re just not to the point where we can release that,” Bloomington Police Capt. Joe Qualters said..

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Authorities are hoping to enhance the video to help investigators identify one or two of the vehicles that appear in the footage.

Qualters said thanks to a tip police were exploring the possibility that Spierer overdosed on cocaine.

“We are not going to focus on one aspect of information that we get in until that information can be corroborated,” Qualters said.

“I don’t know if there’s been any possibility that’s been ruled out at this point,” he added. “It’s absolutely critical for us to remain open-minded about what information we get in, how we treat that information and how we pursue it.”

As for Lauren’s parents, they said they plan to stay in Indiana to wait for Lauren to come home.

“Obviously we’re not giving up,” her father, Robert Spierer, said. “We feel as strong today in our pursuit to find her as we did a week ago.”

“I love you with all my heart and I need you back,” her mother said.

There was also a $100,000 reward for any information that could help solve the case.

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