to peace and liberty if it can be availed of only after the Deportation Board has unjustly trampled upon it, besmirching the citizen's name before the bar of public opinion?     The doctrine of primary jurisdiction of petitioners Board of Commissioners over deportation proceedings is, therefore, not without exception (Calayday vs. Vivo, 33 SCRA 413 [1970]; Vivo vs. Montesa, 24 SCRA 155 [1967]). Judicial intervention, however, should be granted in cases where the claim of citizenship is so substantial that there are reasonable grounds to believe that the claim is correct. In other words, the remedy should be allowed only on sound discretion of a competent court in a proper proceeding (Chua Hiong v. Deportation Board, supra; Co vs. Deportation Board, 78 SCRA 107 [1977]). It appearing from the records that respondent's claim of citizenship is substantial, as We shall show later, judicial intervention should be allowed.45[45]     The present case, as correctly pointed out by petitioners and wrongfully found by the CA, falls within the above-cited exception considering that proof of their Philippine citizenship had been adduced, such as, the identification numbers46[46] issued by the Bureau of Immigration confirming their Philippine citizenship, they have duly exercised and enjoyed all the rights and privileges exclusively accorded to Filipino citizens, i.e., their Philippine passports47[47] issued by the Department of Foreign Affairs.   In BOC v. Dela Rosa, it is required that before judicial intervention is sought, the claim of citizenship of a respondent in a deportation proceeding must 45[45] Id. (Emphasis supplied.) 46[46] Marked as Annexes “D” and “E” in the Comment of petitioners Grace and Geraldine, respectively; CA rollo, 257, 313. 47[47] Copies marked as Annexes “C” and “F,” id.