NEW YORK » A nanny suspected of stabbing two young children to death in a luxury apartment near Central Park was in critical condition today with apparently self-inflicted injuries.

The children’s mother, Marina Krim, came home with her 3-year-old daughter on Thursday evening. Puzzled by the darkened apartment, she returned to the lobby to ask the doorman if the nanny had gone out with 2-year-old Leo, just learning to walk, and 6-year-old Lucia, known as Lulu, lover of "all things princess."

She was told they hadn’t left, so she returned upstairs. The children’s bodies were in the bathtub; the nanny lay wounded nearby. It’s unclear how many times the children were stabbed.

"There was some kind of screaming about, ‘You slit her throat!’" said music therapist Rima Starr, who lives on the same floor and heard screams coming from the apartment at around 5:30 p.m.

The nanny, Yoselyn Ortega, who was found near a knife, remained hospitalized today. She was placed in police custody, but no charges have been filed.

The children’s father, CNBC digital media executive Kevin Krim, had been away on a business trip. Police met him as he arrived at the airport and escorted him to the hospital.

The mother’s blog, called Life with the Little Krim Kids, portrays a devoted mother who adores her children, and is charmed by their daily observations and latest tricks. It is filled with family pictures and the children happily posing together.

In a February entry, Krim writes about visiting their nanny’s family in the Dominican Republic. She refers to the woman as Josie; it’s not clear if it’s the same nanny found wounded Thursday.

"We met Josie’s amazing familia!!! And the Dominican Republic is a wonderful country!!," she wrote.

In an entry from May, she describes Leo’s obsession with his new Crocs.

"Even at nap time — Josie, our nanny, took them off and he screamed bloody murder, so she put them back on and he went right to sleep," she wrote.

On Thursday night, she left the building "inconsolable, hysterical, frantic," another neighbor, Sandy Marcus, told the Wall Street Journal.

The crime scene is in one of the city’s most idyllic neighborhoods, a block from Central Park, near the Museum of Natural History and blocks from Lincoln Center for the Performing Arts. The neighborhood is home to many affluent families, and seeing children accompanied by nannies is an everyday part of life there, making the idea of such violence even more disturbing to residents.

Police Commissioner Raymond Kelly said it’s unclear how long the nanny had worked for the family.

Fernando Mercado, the superintendent of the building where Ortega lives with her sister and niece, told The Wall Street Journal that she is "a very nice woman" and "very religious."

"To me, she has always been very, very stable," he said.

On a webpage devoted to a family wedding, Lulu was described as loving "art projects, ballet, and all things princess." It said Leo was just learning to walk.

The family had moved to New York from San Francisco within the last few years. The children’s father was named general manager of CNBC’s digital media division in March, after working previously in digital media at Bloomberg. Their mother also had a cooking blog and taught art classes to young children.

The family lived in a stately, late 19th-century apartment building where one three-bedroom unit currently available for rent has an asking price of $10,000 per month. They had a greyhound, retired from racing, named Babar.

Associated Press writer David B. Caruso contributed to this report.