BEIJING - Jaycee Chan has admitted to taking marijuana for the past eight years, China Central Television (CCTV) has reported.

Hong Kong superstar Jackie Chan's only son, who was detained last Thursday alongside Taiwanese actor Kai Ko for using and possessing the drug at his Beijing home, told police he had been taking marijuana alone or with friends at home since 2006, CCTV reported in a feature programme aired on Tuesday night.

The 32-year-old said he had his first taste of the drug in the Netherlands, and found it hard to kick the habit, the programme said, citing Beijing police.

Both Jaycee and 23-year-old Ko, who shot to fame in 2011 as the lead in You Are The Apple Of My Eye, tested positive for marijuana on Monday. Police also seized 110g of marijuana in Jaycee's home in Beijing, the CCTV programme said.

Jackie Chan had arrived in Beijing on Monday and was expected to visit his son on Tuesday afternoon, according to reports. The 60-year-old, who was named an anti-drug goodwill ambassador for China in 2009, has yet to speak publicly on the case.

According to CCTV, Ko told the police he tried marijuana for the first time in 2012, at Jaycee's home.

In police footage aired by CCTV on Monday, Ko wept as he apologised for his misdeed.

"I have set the worst example," he said. "I have made a big mistake."

Ko's parents and brother visited him at the Beijing detention centre on Tuesday. His father told reporters he had not taught his son well and apologised on behalf of the family.