Israel has targeted Hamas leader Mohammed Sinwar in a strike on a hospital in southern Gaza on Tuesday evening, according to a senior Israeli official and two sources familiar with the matter.

Israel’s military did not immediately respond to a request for comment. A military spokesman had warned of an impending attack in northern Gaza.

The strike hit an underground site in Khan Younis, according to Israel’s military, and an official said it could take days for Israel to determine whether the strike was successful.