Appeal by defendant from a judgment of the County Court, Nassau County (Plumadore, J.), rendered July 7,1981, convicting him of criminal sale of a controlled substance in the second degree, upon his plea of guilty, and imposing sentence. The appeal brings up *854for review the denial, after a hearing, of that branch of the defendant’s motion which sought to suppress certain oral and written statements made by him to the police. 11 Judgment reversed, on the law and the facts, plea vacated, motion granted, insofar as it is to suppress all of the defendant’s oral and written statements made to the police, and case remitted to the County Court, Nassau County, for further proceedings. H On June 20, 1980, at approximately 7:00 p.m., several detectives assigned to the Long Island Drug Enforcement Task Force were at the intersection of the Long Island Expressway and Little Neck Parkway, near the Nassau-Queens border, in connection with a prearranged plan to purchase cocaine. Shortly after 7:00 p.m., another car approached in which a confidential informant, the defendant and another were seated. After the transaction was consummated, a detective ordered a surveillance unit to arrest everybody in the vehicle. 11 The defendant was removed at gunpoint, patted down, and, prior to the administration of Miranda warnings, was asked by one of the officers, “Do you know what’s going on here?” He responded, “I’m doing a favor for a friend”, indicating, as well, that he was to have made $500 on the deal. The defendant was thereupon transported to the office of the Nassau County Narcotics Squad. H During the trip, Miranda warnings were administered and the defendant stated that “[a] friend of mine asked me if I knew anybody who had cocaine for sale, and I told him I did. I met with [another person arrested at the same time] and we came out here and I was arrested”. He again admitted that he was to have made $500 on the transaction. For the remainder of the trip, the defendant was silent. 11 The defendant and the officers arrived at the office of the Narcotics Squad at about 7:45 p.m. Pedigree and related information was obtained from the defendant, immediately after which the defendant was asked “if he was interested in helping himself” and he answered: “Yes, I’ll do anything”. The detectives indicated that he could help himself if he would tell them and show them who was engaged in selling cocaine. The defendant said that “[i]f you can get me out” he would do so as he knew people “in Florida and * * * in New York”. H The defendant was again advised of his Miranda rights and he initialed a waiver form. He thereupon made a detailed oral confession which was reduced to writing and signed. 11 After a hearing, the County Court suppressed the defendant’s first statement, made on the scene prior to the administration of Miranda warnings (the People assume, without conceding, that suppression of this statement is mandated by People v Quarles, 58 NY2d 664, cert granted_ US_, 103 S Ct 2118), but refused to suppress the subsequent oral statement made in the police vehicle and the oral and written confessions made at the police precinct. We reverse. U Based upon a practical “assessment of external events” we are compelled to conclude that the defendant was “subjected to such a continuous interrogation” that the Miranda warnings subsequently administered “were insufficient to protect his rights” (People v Chappie, 38 NY2d 112,115). We perceive no “definite, pronounced break in the interrogation that the defendant may be said to have returned, in effect, to the status of one who is not under the influence of questioning” {People v Chappie, supra, p 115; see, also, People v Johnson, 64 AD2d 907, affd 48 NY2d 674; People v Glover, 58 AD2d 814). 11 The dissent concedes that suppression of the oral statements made at the scene of the arrest and in the police car is required and agrees that there is a temporal proximity between those oral statements and the oral and written confessions made at the police precinct. Nonetheless, it finds that what it characterizes as “the intervening bargaining acts of the defendant” constitute the requisite break in the chain of events. We cannot agree. 11 As set forth above, the record indicates that the defendant’s purported agreement to help the officers was neither spontaneous nor the result of an independent, voluntary act by the defendant. It was initiated by the arresting officers and rather *855than a break in the interrogation, it was part and parcel of it. H Moreover, we also disagree with the dissenters’ suggestion that a harmless error analysis may be employed, if, as is their view, suppression of only the oral statements made before defendant’s arrival at the police precinct is required. “[W]hen a conviction is based upon a plea of guilty an appellate court will rarely, if ever, be able to determine whether an erroneous denial of a motion to suppress contributed to the defendant’s decision, unless at the time of the plea he states or reveals his reason for pleading guilty” {People v Grant, 45 NY2d 366, 379-380; emphasis added). There is no indication upon which to hinge such a determination here for “a confession is a most serious matter in the trial of a criminal case” and “[i]t is enough * * * to note that the confession was a likely factor which might have induced the plea and might have affected substantially a verdict upon a trial” {People v Ramos, 40 NY2d 610, 618-619; see, also, People v Purdy, 53 NY2d 806; People v Tyler, 99 AD2d 537; but cf. People v Coles, 89 AD2d 471). Titone, J. P., Bracken and Brown, JJ., concur.