NEWARK, N.J., Oct 24: A Pakistani man detained on immigration charges in the US probe of last month’s plane attacks died in his jail cell in New Jersey of an apparent heart condition, officials said on Wednesday.

They said Mohammed Butt, 55, was found lying on his back on his bed early on Tuesday in his cell at the Hudson County jail in Kearny, New Jersey. An official also said between Oct 1 and Oct. 6, the man was treated with an antibiotic after he complained of gum pain and showed signs of gingivitis.

Although officials initially administered a nasal swab on the body to test for anthrax, a test for the potential germ warfare bacteria would not be part of toxicological tests, a spokeswoman for the New Jersey state medical examiner said. The result of the swab test was negative.

“There is no anthrax involved,” said Emily Hornaday, spokeswoman for the New Jersey division of criminal justice, which oversees the medical examiner’s office. “He died of natural causes.

“There is no need to conduct an anthrax test. He was on antibiotics because of gum problems.”—Reuters