Noted San Francisco documentarian Kevin Epps, who was arrested on suspicion of homicide Monday evening following a shooting death in his home, regained his freedom Tuesday. According to the District Attorney's office, investigators have thus far failed to accumulate sufficient evidence in the case, so they won't be charging him at this time.

Best known for his documentary Straight Outta Hunter's Point, Epps has been both an outspoken advocate against police violence and a fixture in the local film scene for years.

As previously reported, police were called to Epps' Glen Park home at around 1:30 Monday afternoon on reports of a shooting. When they arrived, they discovered a man identified by family members as 46-year-old Marcus Polk Sr.. Polk was pronounced dead at the scene. (The SF Medical Examiner has not publicly identified the victim.)

Police arrested the 48-year-old Epps on the spot, booking him into San Francisco County Jail for both the shooting and for being a felon in possession of a firearm. According to the Chron, "It wasn’t immediately clear why Epps was barred from possessing a gun, but Santa Cruz County Superior Court records show he was charged with two felony counts of penetration with a foreign object in 2002."

According to Polk's son, who told CBS 5 that Epps is his stepfather, Polk Sr. "would sometimes show up at the house unannounced," which angered Epps. The Chron reports that Polk Sr. "was a registered sex offender with prior convictions for attempted robbery and domestic battery" and "had entered a spiral of homelessness and drug addiction 10 years ago, when his mother, whom he had been living with, died. He would sporadically show up at the house on Addison Street where two of his children lived, often unwelcome and always causing problems."

Polk's son said Monday that his dad "showed up out of the blue today and from what I’ve been told, he made a comment that ‘she doesn’t really like you.' I think that’s what did it. And [Epps] shot a man in the back.”

Multiple news agencies reported late Tuesday, however, that Epps had been released from jail. According to KRON 4, SF DA's office spokesperson Max Szabo "said there is insufficient evidence to charge the case at this time."

In a statement emailed to media Wednesday afternoon, San Francisco Police Department spokesperson Sargent Mike Andraychak says that "it is not uncommon for the DA's Office to request additional investigation on a case. SFPD investigators work closely with the DA's Office and the SFPD Homicide Detail will be continuing the investigation into this matter."

ABC 7 reporter Vic Lee tweets that the "investigation by DA will continue but so far prosecutors believe they don't have enough evidence to charge" and that the "DA wants results of toxicology tests on Epps and more thorough investigation."

Previously: Noted San Francisco Filmmaker Arrested In Glen Park Homicide