03/13/2007 at 09:00 AM EDT
Sylvester Stallone is facing charges of bringing a banned muscle-building hormone into Australia.
Customs officials had detained the 60-year-old actor and his entourage at Sydney's airport on Feb. 16, searched their bags and confiscated items, the Associated Press reports.
Stallone's hotel room was searched three days later and more items were confiscated.
At the Feb. 17 Sydney premier of Rocky Balboa, Stallone called the airport incident a "misunderstanding."
At a hearing on Tuesday in Sydney – which the actor did not attend – prosecutors charged that Stallone marked "no" on a customs card when asked if he was bringing prohibited items into Australia, but X-rays of his luggage revealed 48 vials of the human growth hormone Jintropin.
Jintropin is considered a performance-enhancing drug in Australia and can only be imported with a special permit from the government. The maximum penalty for bringing it into the country illegally is a fine of $86,000 and five years in prison, but the local court can only impose a $17,000 fine.
The case will be back on April 24, when Stallone's lawyers will be asked to enter a plea on his behalf.
His rep declined to comment to PEOPLE.