Thursday was a sad day for the comedy world. Harris Wittels, the executive producer of NBC's “Parks and Recreation,” was found dead at his Los Angeles home on Thursday after police received a call about a possible overdose, USA Today reported. He was 30.

Wittels had struggled with substance abuse and had been to rehab twice, TMZ reported. His death due to a possible overdose would come as a shock to family and friends as he had recently spoken about being clean and sober. Before his untimely death, he did a stand-up comedy show at “The Meltdown” in Los Angeles.

Rumors that he might have overdosed surfaced after authorities found Wittels lying on a couch in a house filled with drug paraphernalia, TMZ reported. His body did not show any signs of harm. Wittels was pronounced dead at 1 p.m. EST.

Aside from “Parks and Recreation,” Wittels also worked on “The Sarah Silverman Show” and “Eastbound and Down.” In 2012, he wrote a book called “Humblebrag: The Art of False Modesty,” which is a term he came up with.

On his verified Twitter account, Wittels wrote the following: “i love chillin, hangin out, havin fun and just f----n chillin.” His last tweet was on Wednesday. A few days earlier, he had sent out a few jokes to his 86,500 followers.

His friends and colleagues mourned his death on social media.

The NBC hit “Parks and Recreation” is in its final season. The final episode of the series, which stars Amy Poehler, is set to air Tuesday.

Follow me on Twitter @mariamzzarella