A notice u/s 142(1) was served by AO on an assessee on account of his failure to file his return of income within the time limit prescribed u/s 139(1). Since assessee failed to file return of income within the time limit prescribed in the notice, AO completed tthe assessment u/s 144 . However before assessment order could be served on the assessee, he filed a belated return u/s 139(5). AO ignored the return filed and served the assessment order on the assessee. Is action of AO justified?