A former police officer convicted of committing nine murders was executed at the Florida State Prison in Starke Tuesday night, 24 years after his conviction in 1988.

Manuel Pardo, 56, was pronounced dead at 7:47 p.m. EST, 17 minutes after the lethal injunction process had begun, said Ann Howard, spokeswoman for the Florida Department of Corrections, according to the Associated Press.

Pardo was sentenced to death for killing nine people --three women and six men – in the span of three months in 1986.

Pardo committed a series of crimes, including murders and robbery, and maintained a record of his crimes. Federal police had recovered his diary where he had written the details of the crimes along with photographs of the victims and the press cuttings related to the crimes.

Pardo’s attorneys had raised several arguments to block the trial and execution, arguing that he was mentally sick and that the recent change in the combination of drugs used in the execution process in Florida would amount to violation of his civil rights. However, the courts dismissed the pleas.

His last meal consisted of rice, red beans, roasted pork, plantains, avocado, tomato slices with olive oil and pumpkin pie. He drank egg nog and Cuban Coffee.

Pardo’s last message was "Airborne forever. I love you, Michi baby," referring to his daughter, ABC News reported quoting the prison officers. The media couldn’t hear his last words due to a malfunction of the prison sound system, report said.

Pardo was dubbed the "Death Row Romeo" after he had corresponded with many women during his time in prison and even persuaded many of them to send him money. In his last statement, distributed to the media by the prison officers, he said that he was not guilty of killing the three women but only the six men who were drug traffickers.

"I never harmed those 3 women or any female. I took the blame as I knew I was doomed and it made no difference to me, at this time, having 6 or 9 death sentences," he wrote Tuesday, hours before his execution. "I don't want this hanging over my head, especially these last few minutes of life, because my war was against men who were trafficking (sic) in narcotics and no one else!" ABC News reported.

During his trial, he claimed that he had been doing a favor to the society by killing them and his act did not amount to murder as his victims were vermin and not human beings.

Police said most of his victims were involved in drug trafficking.

Pardo started his career with the Navy where he had served between 1974 and 1978. He later joined Florida Highway Patrol and Sweetwater police and was fired from the police department after he had falsely testified in the trial of a colleague accused of drug smuggling.