The chairman of the Arkansas State Medical Board has no memory of a bombing that destroyed his left eye and left him severely burned, a family friend said Wednesday.

Dr. Trent Pierce has mouthed a simple question to his wife in the last few days — what happened? That question could stymie detectives hoping Pierce could provide leads into why someone placed a homemade explosive in the driveway of his West Memphis home.

"She told him there was an explosion. She didn't get into any detail with that," said Scott Ferguson, a West Memphis doctor and family friend. "I know that the law enforcement people don't want her to say too much about it until they get a chance to interview him when he can talk."

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An oxygen tube running down Pierce's throat still prevents him from speaking to investigators, Ferguson said. However, the doctor has been able to nod yes and no to questions and mouth his own queries to family and friends visiting him at the Regional Medical Center in Memphis, Tenn., just across the Mississippi River from West Memphis.

Doctors recently removed bandages covering Pierce's face and he could see out of his right eye, Ferguson said. Pierce will undergo another eye operation Friday and his breathing tube could be removed the next day, Ferguson said.

On Valentine's Day, Pierce was able to put his arm around his wife and "puckered up for a kiss," Ferguson said.

"We thought that was big Valentine's present: that he knew who she was and what she said and what the appropriate response was," Ferguson said. "To be able to do all those functions, that's just very encouraging."

Pierce was injured Feb. 4 in the explosion, as he reached down to move a stray tire from the path of his hybrid Lexus sport-utility vehicle, Ferguson said. The family physician has undergone several operations since the explosion and his body had to fight back against a fever and possible infection late last week, Ferguson said.

Pierce, 54, leads the state Medical Board, which regulates more than 8,000 doctors, 3,000 therapists and nearly 400 osteopaths in Arkansas. Agents with the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives and state police investigators have examined the medical board's disciplinary records, paying close attention to its split decisions. As a habit, Pierce cast a deciding vote only when the board's 12 other members couldn't resolve cases.

Investigators said they will not release any further information about the case until a suspect has been identified or arrested.

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