NEW ORLEANS (AP) _ A policeman trying to rescue a woman who fell into the Mississippi River from a ferry slipped off the boat himself and disappeared, authorities said.

The Mississippi River Bridge Authority policeman, whose name was not released, was assigned to the ferry Tuesday because of Mardi Gras crowds, said MRBA Cpl. George Eberhardt.

Eberhardt said the officer and a deckhand went to the woman's rescue about 7:30 p.m.

''They were trying to pull her up when they fell in,'' he said.

Others on board grabbed the deckhand and the woman and pulled them aboard, Eberhardt said.

A Coast Guard helicopter and boat searched for the officer but found no sign of him, said Coast Guard spokesman Glenn Lamont. The officer was not wearing a life jacket, he said.