Yes, you can end such a marriage under the Dissolution of Muslim Marriage Act 1939 if whereabouts of your husband are not known for a period of four years.
As per Dissolution of Muslim Marriage Act 1939 Section 2. Grounds for decree for dissolution of marriage. A woman married under Muslim Law shall be entitled to obtain a decree for the dissolution of her marriage on any one or more of the following grounds, namely:
(i) that the whereabouts of the husband have not been known for a period of four years;…..
Section 3 is also important:
Notice to be served on heirs of the husband when the husband’s whereabouts are not known. In a suit to which clause (i) of section 2 applies: (a) the names and addresses of the persons who would have been heirs of the husband under Muslim Law if he had died on the date of the filing of the plaint shall be stated in the plaint. (b) notice of the suit shall be served on such persons, and (c) such persons shall have the right to be heard in the suit: Provided that paternal-uncle and brother of the husband, if any, shall be cited as party even if he or they are not heirs.
Some Useful Links on Family Law are below :
Can a wife Divorce her husband in Pakistan? (Column 18 Nikahnama)
A Primer on Child Custody, Interim Custody , Visitation and Guardianship as per Pakistani law
