Chinese police said Wednesday they are investigating the death of an elderly man, after reports that he died following a beating by city enforcement officers triggered outrage online.

The urban management personnel known as "chengguan" enforce local regulations and have a poor reputation in China, where stories of their brutality regularly spark outcries.

The man, aged around 70, tried to mediate in a dispute Wednesday between the officers and a market vendor in Fuzhou city in the eastern province of Fujian, the Strait News said.

The chengguan were suspected of beating him and he died at the scene, the newspaper said on its verified account on China's Twitter-like Sina Weibo.

The newspaper forwarded a posting that quoted witnesses as saying two chengguan chased the man for "dozens of metres". At one point one was strangling him while the other punched him, the poster added.

"We are investigating on the scene," a local police officer surnamed Chen told AFP, confirming that the man was dead but declining to provide any further details.

The incident -- the latest abuse case involving chengguan -- was the third hottest topic on Sina Weibo.

"How do chengguan differ from thugs?" wrote one user. "The first thing that comes into my mind when chengguan are mentioned is beating people. I can't remember how many times I have read about chengguan beating people up."

In one of the highest-profile examples, four chengguan in the central province of Hunan were sentenced to between three and a half and 11 years' jail in December over a dispute that left a roadside watermelon vendor dead.

Local media reported that the officers beat the vendor to death for operating without a licence, with one smashing his head with a metal measuring weight.