According to Mehr News Agency, Javanfekr was released on the same day after consultations between administration officials and the Judiciary.
On Sunday, Khabar Online had reported that a Tehran court has sentenced Javanfekr to one year in prison and banned him from engaging in media activities for three years for publishing articles and pictures in the August 13 special edition of the newspaper Iran deemed to be in violation of Islamic and moral principles.
Reportedly, the execution of Javanfekr's arrest warrant has temporarily been put on hold. Javanfekr is also the manager of the Islamic Republic News Agency (IRNA).
Iranian security forces tried to arrest a senior adviser to President Mahmoud Ahmadinejad on Monday, witnesses said, firing tear gas into the offices of the newspaper that the aide runs and retreating only after a phone call from Ahmadinejad himself.
The incident shows the growing split between Ahmadinejad, who is elected, and the appointed group of Shiite Muslim clerics and Revolutionary Guard Corps commanders who are trying to curb Ahmadinejad's power.
At a news conference in his own newsroom Monday, Javanfekr called publicly for reform, brushing aside warnings he'd been given not to speak out. Javanfekr said that Ahmadinejad fully supports Khamenei, but charged that many clerics who are close to Khamenei are abusing their power.
"We should all be able to say our criticisms," Javanfekr said. "There should not be an atmosphere of strangulation in this country."
A short time later, security forces moved in, apparently to arrest Javanfekr, journalists who were there said. They fired tear gas inside the newsroom and used electronic batons as they moved up the stairs, injuring political editor Ali Reza Soltani, a member of the newspaper's security team said.
Javanfekr was resisting arrest, aided by his journalistic colleagues and the newspaper guards, when the phone call came in from Ahmadinejad and police withdrew, the guard said. In total, 33 people working for the paper were arrested, the guard said.