Iran's reformist government says it is willing to help identify the man that killed Iranian-Canadian journalist, Zahra Kazemi, a spokesman has said.
Kazemi died of head injuries in custody
The intelligence ministry will do so "provided the judiciary allows it," Abdollah Ramezanzadeh told reporters.
The announcement comes two days after the hardline judiciary cleared Mohammad Reza Aghdam Ahmadi of her killing.
Ms Kazemi died in custody in Iran last year. She was arrested after taking pictures outside Tehran's Evin prison.
She died in hospital in the capital on 10 July after falling into a coma, having received head injuries during more than three days of interrogation.
Ms Kazemi's family has previously said a high-ranking official of the justice department struck the fatal blow, and that the court was putting someone else on trial to protect the real killer.
Reformist President Mohammad Khatami had also said he believed Mr Ahmadi, an intelligence ministry agent, was innocent and called on the judiciary to identify "the real guilty person".
"The intelligence ministry is prepared to identify the person behind the semi-premeditated murder of Zahra Kazemi, provided the judiciary allows it to do so," said his government spokesman.
Asked whether the reformist-run intelligence ministry had already identified who was responsible for Kazemi's death, Mr Ramazanzadeh said the ministry believed it "is able to identify (them) and is ready to do it."
In a statement released on Monday, the Iranian judiciary said Mr Ahmadi had been acquitted "due to lack of sufficient evidence".
President Khatami's reformists are vying for power with hardliners
"Firstly, Ahmadi consistently pleaded not guilty all through the trial. Secondly, Kazemi's mother and her lawyers have not directly named him as the murderer. And thirdly, there was no sufficient evidence against him," state news agency Irna quoted the statement as saying.
Zahra Kazemi's son, Stephan Hachemi said the trial was a "cover-up" to divert attention from the real killer.
Lawyers acting for the Kazemi family say they now have 20 days to appeal.
They are calling for the judiciary to appoint a new investigator to look into the case and for the trial to take place at a provincial court.
The case soured relations between Iran and Canada and Ottawa recalled its ambassador in protest.
The case also deepened the rift between Iran's reformist government and the hardline judiciary, with both sides accusing the other of a cover-up.