The authorized period of status of an alien as a nonimmigrant under section
1101
(a)(15)(U) of this title shall be for a period of not more than 4 years, but shall be extended upon certification from a Federal, State, or local law enforcement official, prosecutor, judge, or other Federal, State, or local authority investigating or prosecuting criminal activity described in section
1101
(a)(15)(U)(iii) of this title that the alien’s presence in the United States is required to assist in the investigation or prosecution of such criminal activity. The Secretary of Homeland Security may extend, beyond the 4-year period authorized under this section, the authorized period of status of an alien as a nonimmigrant under section
1101
(a)(15)(U) of this title if the Secretary determines that an extension of such period is warranted due to exceptional circumstances. Such alien’s nonimmigrant status shall be extended beyond the 4-year period authorized under this section if the alien is eligible for relief under section
1255
(m) of this title and is unable to obtain such relief because regulations have not been issued to implement such section and shall be extended during the pendency of an application for adjustment of status under section
1255
(m) of this title. The Secretary may grant work authorization to any alien who has a pending, bona fide application for nonimmigrant status under section
1101
(a)(15)(U) of this title.