This is an appeal from judgments of sentence imposed on convictions of robbery, theft by unlawful taking, and conspiracy. Appellant has raised a substantial issue regarding deprivation of his right to a speedy trial, as delineated in Pa.R.Cr.P. 1100. Since on the record before us we are unable to resolve the issue, we remand for further proceedings.
The charges against appellant were based on an incident at a car wash and gas station on April 1, 1974. A criminal complaint was filed against appellant on the same day, and he was immediately arrested, later being released on bail. On May 27, 1975, 421 days after the complaint was filed, appellant was tried. Before trial he filed a petition requesting that the charges be dismissed because the Commonwealth had failed to bring him to trial within 270 days as required by Rule 1100(a)(1). After a hearing, the lower court denied the petition on the ground that “any delay in going to trial has been caused by the defendant Clark or his attorney, and, therefore, the Court found that he had not been denied his right to a speedy trial.” Opinion of the lower court at 4.
Appellant’s trial was originally set for November 12, 1974, well within the 270 day period.1 The prosecutor and appellant’s counsel appeared in court that day but appellant did not. Appellant’s absence was unexplained, and when the prosecutor suggested that appellant was a fugitive, the court agreed and declared him a fugitive. In fact, however, appellant was in jail in the same county, under charges unrelated to the car wash and gas station incident. Appellant had received notice of his November 12 trial date but had made no effort to inform his counsel, the prosecutor, or the warden regarding his required appearance in court for trial. Although there was some evidence that someone in the District Attorney’s office knew that appellant had been *187rearrested and was in jail,2 evidently the prosecutor in charge of the present case did not.
The case was again listed for trial on March 31, 1975, but was not reached. It was listed again for April 1, but was not reached. On April 4 the court granted a continuance because appellant’s counsel was not present. On May 15 another continuance was granted because appellant’s counsel was not prepared. Appellant’s petition under Rule 1100(f) was heard and denied on May 27, and trial commenced the next day. At no time did the prosecution file a motion to extend the time for commencement of trial. Rule 1100(c).
It is true that even in the absence of an extension of time under Rule 1100(c), the period within which trial must be commenced will be extended by such period as may result from (1) the unavailability of the defendant or his attorney, or (2) any continuance in excess of thirty days granted at the request of the defendant or his attorney. Rule 1100(d). However, in this case, facts crucial to a determination of the proper period were ignored by the court below.
As has been mentioned, on November 12, 1974, the lower court declared appellant a “fugitive.” Clearly, a fugitive is “unavailable” as that word is used in Rule 1100(d)(1).3 But was appellant a fugitive? Some law enforcement official knew that appellant was in jail; probably someone in the District Attorney’s office also knew it. However, those who knew that did not also know that appellant was due for trial on the instant charges on November 12; those who knew about the trial did not know of appellant’s subsequent arrest and imprisonment. We are thus unable to find, on the record before us, that the Commonwealth had discharged its duty to exercise due *188diligence to ascertain appellant’s whereabouts.4 However, if the Commonwealth “lost” appellant, appellant took full advantage of being lost. He alone among the principals of this case knew both where he was and that he was due in court on November 12, and yet he made no effort either to get to court or to tell anyone concerned with his case where he was. Although it is axiomatic that “it is not the defendant’s duty to bring himself to trial,” Commonwealth v. Adams, 237 Pa.Super. 452, 457, 352 A.2d 97, 99 (1975), it does not follow from this axiom that a defendant may hide himself away in some crevice of the criminal justice system. To declare appellant a “fugitive” was unwarranted, given the fact that he was in custody. He may nevertheless have been “unavailable.” A determination of whether he was must await further evidence, particularly on the extent of the District Attorney’s knowledge.5
Assume, however, that further evidence warrants a finding that on November 12, 1974, appellant was “unavailable.” That will not be dispositive of appellant’s Rule 1100 claim, as the lower court apparently believed. It will rather be only the beginning of a proper inquiry.
Rule 1100(d)(1) only serves to extend the period during which trial must be commenced under section (a) of the rule. Commonwealth v. Wade, 240 Pa.Super. 454, 360 A.2d 752 (1976); Commonwealth v. Eller, 232 Pa.Super. 99, 332 A.2d 507 (1975). The total number of days for which a defendant is unavailable must be computed; that number is then added to the applicable period under 1100(a); the total *189is the period within which the defendant must be brought to trial. See Commonwealth v. Bean, 244 Pa.Super. 368, 368 A.2d 765 (1976) (Dissenting Opinion of HOFFMAN, J.). In this case, assuming that appellant was unavailable on November 12, 1974, how long was he unavailable? Sooner or later, we know, the prosecutor became aware of his whereabouts. But when? Again, on the record before us, we cannot answer this question; yet it is only after it is answered that the proper period for commencement of appellant’s trial can be determined. Given the record before us, we have no choice but to vacate the judgments of sentence and remand to the lower court to determine how long the period for commencement of appellant’s trial should have been extended due to appellant’s unavailability. If the court finds that appellant was tried within that period (exclusive of the delays occasioned by appellant’s counsel’s absence and unpreparedness), the judgments of sentence should be re-instated. Otherwise appellant must be discharged.
We therefore vacate the judgments of sentence and remand for proceedings consistent with this opinion.
HOFFMAN, J., files a dissenting opinion. PRICE, J., files a dissenting opinion.. The 270th day after the complaint was filed was Dec. 27, 1974.
. Notes of Testimony of the May 27, 1975, hearing on appellant’s petition under Rule 1100 at 6.
. The Official Comment to Rule 1100(d)(1) states that “the defendant should be deemed unavailable for any period of time during which he could not be apprehended because his whereabouts were unknown and could not be determined by due diligence.”
. See footnote 3, supra.
. In his dissenting opinion, Judge PRICE reasons that since the “Commonwealth” is a unitary concept encompassing all prosecuting officers, all knowledge of any one of those officers must be imputed to all. Such a presumption of omniscience on the part of the government is unreasonable; it would impute to an Assistant District Attorney at one end of a county immediate knowledge of an arrest occurring at the other end. To be sure, sooner or later, one would expect him to find out about it. When he should is the question the lower court should have addressed.