It was incredibly sad news in the wake of the killing of British backpacker Grace Millane, he said.
Thinking of the little boy last night made him especially sad, he said
"I'm so, so, thankful to the lady who was holding him."
He "slowly, slowly" went to sleep in her arms, he said.
The crime scene in Flat Bush remained under cordon at midday today with police officers wearing blue coverall suits conducting what appeared to be a forensic examination.
A post-mortem examination would also take place today.