John Newton Mitchell, the gruff former attorney general who went to prison for conspiring to cover up the Watergate scandal in his friend Richard Nixon's White House, is dead at 75 after collapsing on a Washington street.

Mitchell was the highest ranking of the government officials who served time for the political scandal that brought about Nixon's resignation from the presidency in August 1974."I considered John Mitchell to be one of my few close personal friends," Nixon wrote in his memoirs. "I believed that I owed my election as president in 1968 largely to his strength as a counselor and his skill as a manager."

An ambulance crew, alerted by a 10-year-old boy who was skateboarding, found Mitchell unconscious on a street in the Georgetown section of Washington in the early evening Wednesday. Mitchell had suffered a heart attack.

He stopped breathing as he was being taken to the hospital and died despite cardiopulmonary resuscitation.

Mitchell was convicted on Jan. 1, 1975, of conspiring with Nixon's chief lieutenants, chief of staff H.R. Haldeman and domestic counselor John D. Ehrlichman, to cover up White House involvement in the Watergate affair, of the cover-up itself and of perjury. He fought the conviction in vain before the Supreme Court.

All three were sentenced after a three-month trial to terms of 21/2-to-8 years.

There was testimony at the Senate Watergate hearings, at the cover-up trial and in various published first-person accounts that Mitchell twice rejected plans for spying on Democrats because they were too expensive but that he accepted a third, less expensive, version. Mitchell always denied the allegation.

But in a March 22, 1973, taped Oval Office conversation, Ehrlichman said "John says he's sorry he sent those burglars in there" to which Nixon replied: "That's right."

Mitchell chimed in at that point and said "You are very welcome, sir," and the transcript shows laughter.

The tapes also showed that Nixon once wanted Mitchell to take the rap for the entire Watergate cover-up. But Mitchell never said a harsh word about his former New York law partner and would not permit his defense lawyer to do so. By all accounts they remained friends.

"He was very loyal to the president and the president was not very loyal to him," the late Sen. Sam Ervin, who presided over the Watergate hearings in the Senate, once said.

Mitchell was the first former attorney general to be convicted of a crime. He was disbarred and served a 19-month prison term, which included five months of medical furloughs.