Disability insurer Aflac Inc fired comedian Gilbert Gottfried as the voice of its iconic duck on Monday after a series of Twitter jokes about the earthquake in Japan, Aflac's most important market.

Since 2000, Gottfried has voiced the duck in the insurer's TV ad campaign in the United States, quacking Af-LAC! in the comedian's famously abrasive voice.

Gottfried fired off a dozen jokes on the social media service over the weekend, all riffing in one way or another on the devastating earthquake and subsequent tsunami. One joke suggested Japan needed an urgent shipment of rubber ducks, though many tended toward the crude and sexual.

The company said his comments were lacking in humor and certainly do not represent the thoughts and feelings of anyone at Aflac.

Aflac said it would start a nationwide casting call to find a new voice -- and noted that it was already using a different voice in the Japanese market, where it is the No. 1 foreign insurer.

The company made its name selling cancer expense policies in Japan in the 1970s, and still derives about three-quarters of its revenue in the country.

Gottfried's agent was not immediately available to comment.

(Reporting by Ben Berkowitz; Editing by Richard Chang, Gary Hill)

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