A Chinese army general has apologised for his son's brutal beating of a couple and offered compensation, state media said Friday, in the latest scandal involving the so-called "rich second generation".

The case, which has sparked widespread outrage, is reminiscent of a high-profile scandal last year, when the son of a top police officer tried to use his father's status to escape a deadly car accident he had caused.

According to the official Global Times paper, police detained Li Tianyi, 15, Tuesday in Beijing after witnesses said he and a friend leapt from their sports cars and beat a man and woman for three minutes while their son looked on.

Li reportedly has no driving licence and his car, a customised BMW coupe, had no licence plate. But a lawyer told the English-language daily that he would not be charged because he was not yet 16 years old.

The woman who was beaten up by Li and the other boy, surnamed Su, told the newspaper that her husband had to have nine stitches to his forehead and two to the back of his head, and that he suffered wounds to his nose and right eye.

General Li Shuangjiang, 72, a famous singer and music department dean at the Beijing-based PLA Academy of Arts, apologised for his son's actions.

"As the father, I bear the responsibility for my son's behaviour. I'm so sorry that I'd rather now be beaten by you," he was quoted as saying.

"I will not condone my son's faults, and there will be a settlement."

Police in Beijing's Haidian district, where the incident occurred, were not immediately available for comment.

Witnesses said that Li and Su beat up the couple in what appeared to be an act of road rage.

"Who will dare call the police?" they shouted to stunned onlookers before trying to flee the scene. They were stopped by local residents, the report said.

The incident has sparked lightning-fast online calls to punish Li, amid disgust over what some see as the brazen high-handedness of top officials and their families.

One user of Sina Weibo, China's most popular Twitter-like microblog -- which had more than 150,000 messages about the incident -- hit out at the general.

"What kind of a person is Li Shuangjiang? His son is only 15 but drives a BMW with a gun. What is wrong with China?" the online user said, referring to a toy gun reportedly found with the young Li when he was detained.

"Great," said another netizen. "It's because China has people like these that it's corrupt."

In last year's scandal, the 22-year-old police officer's son ran over a student in the northern province of Hebei and infamously shouted: "Sue me if you dare. My father is Li Gang!" He was later sentenced to six years in prison.

In June this year, China executed a music student who stabbed a woman to death after he hit her with his car because he feared the "peasant woman would be hard to deal with" over the accident.

The victim only suffered minor injuries in the accident but Yao Jiaxin, a student at the Xian Conservatory of Music, stabbed her eight times with a knife as she eyed his car number plate.

The cases have turned an increasingly bright spotlight on the dubious reputation of China's "rich second generation" -- a term applied to the spoiled offspring of powerful beneficiaries of China's 30-year economic boom.