Jury selection has begun for an Ohio doctor charged in the 2005 cyanide poisoning of his wife.

The judge in the Cleveland trial of 41-year-old Yazeed Essa warned prospective jurors on Tuesday that the case could last up to seven weeks.

Essa has pleaded not guilty to aggravated murder.

Prosecutors say Essa gave his 38-year-old wife, a former nurse, a capsule containing cyanide that she thought it was a calcium pill. After taking the capsule, the sport utility vehicle she was driving crashed and she was pronounced dead at a hospital.

Essa left the country after his wife's death and was arrested in 2006 in Cyprus. He gave up a long extradition fight and was returned to Ohio last year.