Man convicted of killing sex partner, lighting him on fire arrested again for arson

A 25-year-old man convicted of involuntary manslaughter after allegedly killing a sexual partner and setting his body on fire in San Francisco's Buena Vista Park in 2011 was arrested Wednesday on suspicion of another act of arson, police said today.

The arson suspect, David Munoz Diaz, was arrested Wednesday for allegedly starting a fire early Saturday morning in front of businesses located in the 4000 block of 18th Street, about a block from Castro Street, according to San Francisco police Officer Grace Gatpandan.

A storage room was reported to be on fire shortly before 5:30 a.m., Gatpandan said.

Fire officials responded and determined that the fire may have been caused intentionally, leading to an arson investigation. Officers arrested Diaz a couple of blocks away on Wednesday night on suspicion of arson, Gatpandan said.

Diaz was booked into jail on suspicion of felony arson, felony possession of a flammable material and first-degree burglary, according to Gatpandan.

A San Francisco jury previously found Diaz guilty of involuntary manslaughter but acquitted him of murder last August for the death of 23-year-old Freddy Roberto Canul-Arguello, whose body was set on fire in Buena Vista Park on June 10, 2011.

San Francisco Public Defender Jeff Adachi said Diaz was charged with fatally choking a sexual partner but had no previous criminal history and no motive to kill the victim.

According to Adachi, Diaz and Canul-Arguello were allegedly acquaintances who previously had a sexual encounter.

The night Canul-Arguello died, the two men had run into each other while in the Castro neighborhood that night and decided to walk to Buena Vista Park to have sex.

Adachi said that during the sexual encounter, Canul-Arguello asked Diaz to choke him. Diaz reluctantly agreed but accidentally asphyxiated him.

Diaz's attorney, Deputy Public Defender Alex Lilien, said the death was accidental and the sexual encounter consensual.

According to the district attorney's office, Diaz panicked and then burned the body, leaving it in a blue recycling bin near the park's tennis courts just off of Buena Vista Avenue East near Haight Street.

Diaz's lawyer said jurors deliberated for six days before finding Diaz not guilty of murder. The jury did find Diaz guilty of involuntary manslaughter, a charge that carries a maximum sentence of four years. Diaz had served more than three years while awaiting trial, Adachi said.

Diaz was also found guilty of arson, mutilation of the remains of a human being and destroying evidence, according to the district attorney's office.

Gatpandan did not say what evidence led officers to arrest Diaz in connection with the fire over the weekend.

<p> San Francisco District Attorney's Office spokesman Max Szabo said Diaz was sentenced to four years on Nov. 14 and, given his time in custody and credits accumulated, he was released on or shortly after his sentencing date.

Bay Area NewsCrimeCrime & CourtsDavid Munoz DiazFreddy Roberto Canul-ArguelloSan Francisco Public Defender's Office

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