A 22-year-old man was dead after a mysterious single-car crash in San Jose early Sunday morning that no one witnessed.

Around 2:46 a.m., a San Jose police officer heard a loud crash on 1^st St and drove over to the area to investigate.

The officer arrived to discover a blue BMW, flipped onto its roof, on the side of the road near the intersection of S. 1^st and Margaret streets, not from an I-280 off-ramp.

It appeared that the vehicle had sheared off two lamp posts before driving up the embankment and flipping ont its roof.

The driver was trapped inside, the roof having collapsed on him.

He was pronounced dead at the scene around 3 a.m.

The crash forced the closure of several streets in the area while the cause was under investigation.

Investigators said it was unclear later that morning whether the rainy weather was to blame, as there were no witnesses to the accident.

"Weather could've played a factor -- I don't know what the rain was like at the time of the accident," said Sgt. Matt Christian of the San Jose Police Department. "There's no standing water, but there is water down there."

Christian said that there were no outward signs of alcohol use at the scene.

Around 8 a.m., the roads surrounding the scene were re-opened.

The crash was San Jose's second traffic fatality of 2013. SJPD's Traffic Investigations Unit was still investigating the crash Sunday. Anyone with information about the crash was urged to contact Detective Eric Dragoo #3191 of the San Jose Police Department's Traffic Investigations Unit, at (408) 277-4654.