Hollywood star Sylvester Stallone was formally convicted Monday of importing restricted muscle-building hormones into Australia and ordered to pay more than £5,000.

New South Wales state Deputy Chief Magistrate Paul Cloran said the "Rocky" and "Rambo" star failed to show he had a valid prescription for dozens of vials of human growth hormone found in his luggage when he arrived in Sydney for a promotional tour in February.

Stallone, 60, had also failed to declare the male hormone testosterone on a customs entry form, although he had legitimate medical reasons for carrying the drug.

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The Rocky star has been fined for importing importing banned drugs to Australia

Calls to Stallone's publicist, Michelle Bega, were not immediately returned.

The magistrate said because of the negative publicity surrounding the case, the penalty was enough to send a clear message that such behavior would not be tolerated.

"I don't think there is anything further the court could or should do in order to deter Mr. Stallone from committing these offenses again," Cloran said.

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Stallone, on set of his upcoming flick John Rambo, said he needed the substance to give his 'body a boost'

Stallone was charged after a customs search of his luggage at the start of a three-day visit to Sydney in February revealed 48 vials of the human growth hormone drug, Jintropin.

The actor told customs officers he had purchased the drugs at a Los Angeles pharmacy, but did not have the prescription with him.

Three days later, Stallone threw four vials of the male hormone testosterone from his Sydney hotel room when customs officials arrived to search it.

Cloran said Jintropin is not legally available for sale in the United States, and found that Stallone had been "untruthful about the existence of a prescription."

However, citing testimony from Stallone's Beverly Hills-based doctor, Robert Huizenga, Cloran found that Stallone had been using the testosterone legally under medical supervision, although he had failed to declare it to customs officials.

In a letter to the court in which he apologized for a "terrible mistake," Stallone said he had taken the drugs for years to treat a medical condition that he didn't disclose.

In an interview with customs officials after the growth hormone was discovered in his bags, Stallone said he was carrying such a large amount of the drug because he was about to go on location in Thailand and Myanmar - also called Burma - for three months to shoot the latest installment of the "Rambo" series.

"As you get older, the pituitary gland slows and you feel older, your bones narrow. This stuff gives your body a boost and you feel and look good," court documents quoted him as saying.

"Doing 'Rambo' is hard work ... Where do you think I am going to get this stuff in Burma?"

Human growth hormone is a naturally occurring substance produced by the pituitary gland. The hormone can be replicated synthetically and is often used to build muscle mass.

It is considered a performance-enhancing drug in Australia and cannot be imported without a permit.

The maximum penalty for bringing Jintropin into Australia without a license is a fine of £45,800 and five years in prison.

But Stallone faced a maximum penalty of £9,100 on each of the two charges and no prison time because the matter was heard in a local, not federal, court.

A senior official with the Australian Customs Service, Robert Janeczko, welcomed the decision.

"I think it's a good outcome. The two criminal convictions show that whether your name is Smith or Stallone you can't bring prohibited imports into this country," he said.

Stallone's lawyers did not immediately comment on the decision.