No one was injured in the incident early Monday outside the administrative offices of Esphigmenou Monastery, and no arrests were reported. The bailiffs withdrew from the site.
Cell phone video of part of the incident, taken by the rebel monks and seen by the Associated Press, showed the court-appointed bailiffs using a small earth-moving machine in an unsuccessful attempt to force their way into the grounds of the office at Karyes, the capital of the all-male sanctuary from where its 20 monasteries are run.
About 100 monks in the 1,000-year-old Esphigmenou monastery have been involved in a years-old dispute with the spiritual leader of the world's Orthodox Christians, Ecumenical Patriarch Bartholomew I, over his efforts to improve relations with the Vatican.
The monks have defied court orders to leave the monastery and allow church-appointed replacements to take over the site and the Karyes offices about 25 kilometers (15 miles) to the south.
"According to the information we have received from the police, explosive materials were thrown at the bailiffs," Aristos Kasmiroglou, civilian governor of Mount Athos, told the AP.
"The law must apply to everyone. And all sides must safeguard the pious nature of the site."
The Esphigmenou monks who argue that they are safeguarding centuries-old Orthodox traditions have refused to leave the complex, and receive food and other assistance from supporters in other parts of Greece.
"They came in the morning and started banging on the doors," Esphigmenou monk Elder Savvas, who said he witnessed the incident, told the AP
"We had warned them that if they provoked us, we would respond."
He did not refer to other details of the incident. But a group supporting the Esphigmenou monks, based in the United States, late Monday denied that the monks had thrown petrol bombs or responded aggressively.
"It appears Greek government officials are trying to cover up their complicity in these lawless and criminal activities by spreading false reports to media outlets," John Rigas, of the group Friends of Esphigmenou, wrote in an email to the AP.