"According to a preliminary report, no traces of beating were seen on his body," Ala'edin Borujerdi, head of the Iranian Parliament's national security and foreign policy committees, told the semiofficial Islamic Students News Agency.
Still, Borujerdi called for further investigation into the case.
The inquiry into the death of Beheshti, 35, is a rare instance in which Iran's Parliament and judiciary followed up on a human rights complaint first raised internationally, The New York Times reported Monday.
Beheshti was held in Kahrizak police prison, near Tehran, and died of natural causes, the judiciary said.
"His body showed no fractures of bones, nor did his skull," judiciary spokesman Gholam Hossein Mohseni Ejei said Monday at a news conference.
Although regarded a relatively minor figure in Iran's blogging environment, Beheshti's death sparked outrage among both opponents and supporters of Iran's government, the newspaper noted. Opposition media claimed he was tortured and pro-government commentators were upset the state-run news media ignored the matter for days, suggesting indifference on the part of authorities.