LONDON (AP) _ A cleaning supervisor has become the first fatality among 34 known cases of Legionnaires' disease in an outbreak at British Broadcasting Corp. headquarters, the BBC says.

Forty-four other cases are suspected in the outbreak in and around the BBC, and six of the remaining 33 confirmed victims are seriously ill, the borough of Westminster said.

Jim Morgan, who supervised cleaning operations in headquarters buildings in central London, was admitted to a hospital two weeks ago, one of the first cases in the outbreak, and died Thursday. He was 63.

Legionnaires' disease, which produces symptoms similar to pneumonia, is often caused by bacteria from water-cooled air conditioning units.

The BBC said its air systems in the Broadcasting House and a nearby building have been disinfected.

The disease was first diagnosed in 1976 after 221 people contracted it in Philadelphia, and it takes its name from the outbreak at the Pennsylvania American Legion convention there.