Senior U.S. lawmakers on Sunday said that investigators have found no evidence thus far pointing to terrorism in the disappearance of Malaysia Airlines Flight MH370 three weeks ago, and that it is critical to find the plane to understand what happened on board.

House Intelligence Committee Chairman Mike Rogers and Senate Intelligence Committee Chairman Dianne Feinstein, speaking on Sunday talk shows, said they had seen no evidence of foul play.

"I have seen nothing yet that comes out of the investigation that would lead me to conclude that (this was) . . . anything other than a normal flight that something happened and something went wrong," Rogers told "Fox News Sunday."