CLEVELAND -- The family of a nurse who was murdered in downtown Cleveland in March has announced a $50,000 Crime Stoppers reward for information leading to the arrest of the person responsible.

Family and friends held a news conference at noon in the area where Aliza Sherman, 53, was fatally stabbed on March 24.

Sherman was on her way to her divorce attorney's office when she was attacked. The reward had been $25,000.

The additional $25,000 was raised by Sherman's family members, siblings and friends.

Jennifer Sherman says her mother deserves justice and "(the) monsters who killed her must be found."

What happened on Erieview Plaza has changed Jennifer.

"I come here and I become numb instantly," she said about the area outside the Galleria.

Losing her mom has made her stronger, sadder and forced her to grow up and take care of her siblings. It's made her a crusader for women and the violence against them.

"This is the first time I'm here, on my own two feet, walking it. I've driven past it multiple times but I didn't have the courage to get out," Jennifer said.

Tuesday she and Justice for Aliza supporters met at Erieview to announce the increased reward money.

More than five months after Aliza Sherman's stabbing death downtown, there are no suspects and no answers.

"As the police have said, everything was left in place. They left her purse, her cash, her jewelry, her car. Everything was untouched except for her," Jennifer said. "And to me, it just shows that there was clearly ... somebody was on a mission."

Crime Stoppers has taken nearly 100 calls on the case.

"A lot of inquiries, a lot of suggestions, but nothing concrete so far," said Cuyahoga County sheriff's Sgt. Dave Rutt.

"It's an active, open investigation that we are committed to resolving," said detective Ed Tomba with Cleveland police.

Tomba sayssurveillance video has been enhanced and examined by experts, but not even a gender or race can be determined for a possible suspect.

"We didn't have a lot to go on in the beginning so I'd have to point to that as one of our challenges," Tomba said, citing the place and time of day as a challenge to find potential witnesses.

Aliza's contentious divorce trial, set to start two days after her death March 24, has raised questions.

Her estranged husband, Sanford Sherman, hired a criminal defense attorney, but police do not call him a person of interest.

"Put it this way: Nobody is ruled out. We don't have a suspect. Everybody and anybody that's it," said Tomba. "That's an issue with the family that they are dealing with, but nobody is ruled out at this time."

Jenn says the monsters who killed her must be found, and she's confident that will happen.

"It's extremely frustrating, and I would be lying if I said it didn't get me down a lot, but in my heart I have such a strong belief and I know that justice will prevail," she said. "I know that there is somebody out there that knows something about this, was a part of it, saw something, heard about it from somebody, and I just encourage that person or those people to please do the right thing."

You can submit a tip anonymously to Crime Stoppers by clicking HERE. If your tip leads to an arrest in the case, Crime Stoppers will deliver the money using a code number, without ever knowing your name. Crime Stoppers says this is the largest reward in recent memory.