In a juvenile delinquency proceeding pursuant to Family Court Act article 3, Mateo F. appeals from an order of disposition of the Family Court, Kings County (Calabrese, J.), dated November 16, 2010, which, upon a fact-finding order of the same court dated September 17, 2010, made after a hearing, finding that he committed an act constituting unlawful possession of weapons by persons under 16 and an act which, if committed by an adult, would have constituted the crime of criminal possession of a weapon in the fourth degree, adjudged him to be a juvenile delinquent and placed him in the custody of the New York State Office of Children and Family Services for a period of 12 months. The appeal from the order of disposition brings up for review the fact-finding order and the denial, after a hearing, of the appellant’s motion to suppress physical evidence.
Ordered that the appeal from so much of the order of disposition as placed the appellant in the custody of the New York State Office of Children and Family Services for a period of 12 months is dismissed as academic, without costs or disbursements, as the period of placement has expired; and it is further,
*1315Ordered that the order of disposition is affirmed insofar as reviewed, without costs or disbursements.
The testimony at the suppression hearing established that, on an evening in April 2010, the arresting officer and his partner were on patrol in an unmarked vehicle and observed the appellant on a city street wearing a backpack and clothing of a color and style typically worn by youths associated with a gang. The appellant was walking with another youth, who was observed to have a bulge in a left front pocket. The two officers, who were in uniform, alighted from their vehicle and walked behind the two youths. When the arresting officer was within five feet of the appellant, he observed a portion of what appeared to be the curved end of a black handle of a knife protruding from an open-ended compartment which ran the length of the bottom of the backpack. When the arresting officer testified, the handle was measured in court and determined to be one inch thick, and the length of the protruding portion of the handle was determined to be more than 2V2 inches. The arresting officer testified that he was very familiar with this type of backpack and had made many arrests for knives carried in this type of bag. After telling the appellant to stop and place his hands on a wall, the arresting officer placed his left hand on the appellant’s upper back or shoulder to ensure that the appellant did not move, while the arresting officer pulled the knife from the backpack with his right hand. The knife was 13 inches long with an 8-inch blade.
The sole contention raised by the appellant on appeal is that the Family Court erred in denying his motion to suppress the knife. Contrary to this contention, on the record presented, the police officers acted reasonably at all times (see People v Brannon, 16 NY3d 596, 600-601 [2011]; People v Herrera, 76 AD3d 891, 893 [2010], affd 16 NY3d 881 [2011]) and, consequently, suppression was not warranted.
While we agree with our dissenting colleague that the level of the intrusion here required a reasonable suspicion that the appellant was committing a crime (see generally People v De Bour, 40 NY2d 210, 223 [1976]), we disagree with her view that the arresting officer did not have sufficient knowledge of facts giving rise to a reasonable suspicion that the appellant possessed an illegal or “dangerous knife” (Penal Law § 265.01 [2]) under circumstances indicating that the appellant considered it to be a weapon rather than a kitchen knife or other utilitarian article (see Matter of Jamie D., 59 NY2d 589, 593 [1983]; Matter of Michael Grudge M., 80 AD3d 614, 615 [2011]).
As established by a courtroom demonstration of the manner *1316in which the knife was positioned when the arresting officer first observed it, the officer reasonably inferred from the size and shape of the handle, and the portion that protruded from the compartment, that the handle was part of a large knife with a long blade. This demonstration and the testimony also established, as the Family Court found, that the knife was “easily accessible” to the appellant. The knife was in a pocket of the backpack facing the appellant’s lower back, which the officer described as a “secret compartment” running the length of the backpack in the “lower back area,” with “an entrance and exit to both sides.” The appellant was wearing the backpack with both shoulder straps, and when so worn, the handle of the knife could be grabbed and the knife easily extracted from the open-ended compartment in the lower back. These observations, coupled with the arresting officer’s knowledge of the types and colors of clothing worn by members of a certain gang, and his personal experience making arrests in that location for the possession of illegal knives carried in this particular type of backpack, gave the officer reasonable suspicion to believe that the appellant was carrying a dangerous knife.
Accordingly, the Family Court properly denied the appellant’s motion to suppress physical evidence. Angiolillo, J.E, Balkin, and Dickerson, JJ., concur.