Neighbors of Dan Gordon-Levitt say he had been taking drugs before his death, RadarOnline.com has exclusively learned.

Dan - the older brother of actor Joseph Gordon-Levitt - had been staying with his girlfriend and a friend at an apartment in Hollywood, California.

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His body was discovered Monday, October 4th at 3:58 a.m. He was 36-years-old.

A neighbor told RadarOnline.com, "They ( Dan and his friends) had been partying, and we were woken up with the girl screaming.

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"She came running out to the front garden of their apartment and some people went out to help her.

"The paramedics were called, but he was found dead surrounded by needles and syringes.

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"He had been living here on and off for the past few years, and he and his friends were not very popular to tell you the truth.

"One time they set a car on fire infront of the building, and there was always groups of people coming and going from that apartment.

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"I'm sorry that he died, but I'm honestly not that surprised either.

On Wednesday, the apartment lay empty with a red sheet over one of the windows.

A Los Angeles Coroner's blue tag was on the front door, marking it as a the scene of an investigation.

Earlier Wednesday, RadarOnline.com exclusively reported that a police source - who was at the scene of the Hollywood apartment where Dan's body was found-told us his death was drug-related.

The source added that the case is now closed.

Coroner spokesman Ed Winter said the autopsy has been completed, but results of the autopsy are being deferred pending toxicology results. 

As RadarOnline.com previously reported, on Tuesday night, Joseph Gordon-Levitt Tweeted: "My super hero brother @burningdan 1974-2010," the 500 Days Of Summer star Tweeted. Celebrate his life here ~ http://bit.ly/dBTMQ8 because he's f**king awesome."

Dan Gordon-Levitt -- also known as Burning Dan -- worked professionally as a performer, as well as a fire-spinning and flow arts teacher in Venice Beach, California. He had a Web site touting his wares at www.burningdan.net.

Joseph Gordon-Levitt recently starred opposite Leonardo Dicaprio, Ellen Page, and Marion Cotillard in the smash hit Inception. His other work includes the critically acclaimed 500 Days of Summer, Killshot, and the television show Third Rock From The Sun.

As suspected, the older brother of Inception star Joseph Gordon-Levitt did die of a drug overdose, RadarOnline.com has exclusively learned.

A police source - who was at the scene of the Hollywood apartment where the body of Dan Gordon-Levitt was found - confirmed his death was drug-related.

The source added that the case is now closed.

As RadarOnline.com previously reported, officials from the L.A. County Coroner's office earlier Wednesday said that drugs were suspected in Gordon-Levitt's death. According to Coroner's spokesperson Ed Winter, Dan Gordon-Levitt, 36, was pronounced dead on Monday, October 4 at 3:58 a.m. in Hollywood.

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Winter said the autopsy has been completed,  but  results of the autopsy are being deferred pending toxicology results. Dan Gordon-Levitt was with two other friends at the time, Winter said, and one was taken to a nearby hospital.

As RadarOnline.com previously reported, on Tuesday night, Joseph Gordon-Levitt Tweeted: "My super hero brother @burningdan 1974-2010," the 500 Days Of Summer star Tweeted. Celebrate his life here ~ http://bit.ly/dBTMQ8 because he's f**king awesome."

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Dan Gordon-Levitt -- also known as Burning Dan -- worked professionally as a performer, as well as a fire-spinning and flow arts teacher in Venice Beach, California. He had a Web site touting his wares at www.burningdan.net.

Joseph Gordon-Levitt recently starred opposite Leonardo Dicaprio, Ellen Page, and Marion Cotillard in the smash hit Inception. His other work includes the critically acclaimed 500 Days of Summer, Killshot, and the television show Third Rock From The Sun.

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Joseph later wrote on his Website hitRECord.org, "BURNING dAN brightly embodied that bold beastly bliss sometimes referred to as 'the creative spirit. "He would absolutely positively insist that we not let this bad news deter us on our collective mission."

Dan Gordon-Levitt spoke to our friends at PopEater lees than two months ago on the heels of his brother's performance in Inception.

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He dished to the Web site about his passion for Flow arts ("a combination of performance art and dance and meditation and yoga and sort of self-transformation") and the uncanny resemblance he bared to his brother.

"Its wonderful to be mistaken for him," Dan told the Web site in the August 11 interview. "He taught me to question the relationships other people have with their siblings because he would be my favorite person in the world even if I wasn't lucky enough to know him as my brother."

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Dan held little back when talking about his fondness for his brother, as there was clearly no sibling rivalry between the pair, just love and support.

"He's just awesome in every way that I pay attention to," Dan said of Joseph. "I ask myself, 'Do I love him because he's my brother or is he really that awesome?' He's really, really awesome ... its rare that I don't feel really proud of him."

Officials from the L.A. County Coroner's office said Wednesday that drugs are suspected in the death of Joseph Gordon-Levitt's older brother Dan Gordon-Levitt, RadarOnline.com has learned.

According to Coroner's spokesperson Ed Winter, Dan Gordon-Levitt, 36, was pronounced dead on October 4 at 3:58 a.m. in Hollywood.

The autopsy has been completed, Winter said, and results of the autopsy are being deferred pending toxicology results. Dan Gordon-Levitt was with two other friends at the time, Winter said, and one was taken to a nearby hospital.