* Mother saw bodies in bathtub as nanny stabbed herself
* Nanny in critical condition in hospital
By Chris Francescani
NEW YORK, Oct 26 (Reuters) - The nanny suspected of slaying a Manhattan professional couple's two young children began stabbing herself as the mother entered the bathroom and began screaming when she saw the dead bodies in the bathtub, New York's police commissioner said on Friday.
The nanny, YoSelyn Ortega, had been employed by the family of Kevin and Marina Krim for two years before she killed their children and attempted suicide on Thursday in the family's luxury apartment, Police Commissioner Ray Kelly said.
Ortega, who lived with her son and sister near the Krims' apartment off Central Park, has been a naturalized U.S. citizen for a decade, Kelly said, adding that she had been referred to the Krims by another family.
New York police were hoping to interview the critically wounded nanny later on Friday, said an NYPD official who requested anonymity. Ortega, 50, has not been charged because police have not been able to interview her.
"We know now that the nanny began to stab herself as the woman entered the bathroom," Kelly said. "We initially thought it was, it had already been done, but now information is coming out that she did it as the mother entered the room."
Ortega remains the prime suspect in the stabbing death of the two children, Leo, 2, and Lulu, 6, Kelly said.
Marina Krim had entered the apartment at about 5:30 p.m. Thursday with her 3-year-old daughter, returning home after Ortega failed to meet her as planned at a local dance studio with the two other children.
Krim saw that the apartment was dark and returned to the lobby to ask the doorman if the nanny and kids had gone out, Kelly said. The doorman said no, and she returned to the apartment and went into the bathroom, he said.
Police spokesman Paul Browne said the children suffered "multiple stab wounds," and were pronounced dead after being rushed to a nearby hospital.
Kevin Krim, the children's father and an executive with CNBC, had been heading home from a business trip, He was met by police at the airport and notified of the killings, police said.
A spokesman for CNBC released a statement Friday expressing the "sadness we all feel" for Krim and his wife. The couple's "unimaginable loss ... is without measure."
Marina Krim, whose Facebook page lists her as originally being from Manhattan Beach, California, taught art classes to children, according to a website for the Hippo Playground Project, a New York organization where she volunteered.
She also maintained a photograph-laden blog to document her daily life with her children, with the final entry dated Thursday, three hours before the discovery.
"Leo speaks in the most adorable way possible," she wrote. "And he does things like, '(I) want a fresh bagel' and 'Lito (what he calls himself) wants cold milk' and most adorable of all, 'No thank you' - he never uses 'No' alone, it's always paired with 'thank you.'"
The blog was later blocked from public view.
A source at NBC News confirmed that the blog - which contains pictures of the Krim family - was Krim's.