New York City police are looking for a woman suspected of pushing a well-known 87-year old singing coach from behind. She was taken to the hospital in critical condition.

New York Police Department released video of the suspect. He was wearing a dark jacket, long white dress, and long, rust-colored hair at the time of Thursday night’s attack.

According to police, the suspect approached the victim at West 28th Street and 8th Avenue. He pushed her from behind, which caused her to fall on her head. The suspect fled towards 9th Avenue.

On Facebook, the grandson of the victim wrote that Barbara Maier Gustern had suffered traumatic brain damage and was now unconscious.

“Should she wake up, she will most likely have speech problems and may not be able to move her right hand. It is a serious injury,” said the grandson, who identified him as AJ.

Gustern is a well-respected actor in New York’s theatre community. The New York Times reported that she coached the cast in the Broadway revival of “Oklahoma!”. She was also once the coach of Debbie Harry, the rock singer from Blondie.

Friends informed the newspaper that Gustern was heading to Joe’s Pub at The Public Theater on Thursday to watch one of her students perform.

Gustern was found outside Gustern’s lobby door by a group of people who were practicing a cabaret show. After the attack, a bicyclist helped Gustern to return to her apartment.

Gustern had shared earlier in the day on Facebook that she felt disconnected from her singing. She was feeling better and excited about the rehearsal and the upcoming show at Don’t Tell Mama, Hell’s Kitchen.

Next was Gustern’s great-grandson.

“I would not ask you to visit her. It is an ongoing investigation, and the police do not want anyone but their family visiting. He wrote to her friends, “And none of you want her to see this, believe me.”

He said that he was “incomprehensibly broke inside.”

AJ wrote, “I struggle to comprehend and cope with the world on a day-to-day basis, and frankly this I am beyond my capacity to bear.”