Decision reserved, case held and matter remitted to Erie County Court for further proceedings in accordance with memorandum: At the time defendant pleaded guilty to a reduced charge of manslaughter in the first degree, defendant admitted that he had "shot somebody" but asserted that his actions were in self-defense. This assertion should have triggered a further inquiry by the trial court as to the circumstances surrounding the commission of the crime and the availability of any defenses. (People v Serrano, 15 N.Y.2d 304.) Such an inquiry was necessary to determine whether defendant's plea was voluntarily and knowingly made (see People v Selikoff, 35 N.Y.2d 227; People v Nixon, 21 N.Y.2d 338).