SHANGHAI, July 19 -- BEIJING TV Station apologized today on its evening news program for a fake report that a local vendor stuffed cardboard instead of pork into steamed buns.

The station said one of its temporary employees was detained by police on Monday. The man, who was identified by his surname Zi, cooked up the report, it said.

"Since the news was issued, Beijing's food safety watchdog and industrial and commercial administration began a city-wide inspection over every dim-sum booth, but they found no illegal deals," according to the statement.

Beijing's public security authority organized a special investigation team over the issue.

Zi, from a life-style channel with the station, was found to have directed a video that showed vividly how the cardboard-filled buns were made merely with a home digital video camera, the TV station said.

Zi has admitted to police that he brought the pork, flour and cardboard to a residential area in rural Beijing in June and visited there twice, the TV station said.

Zi told four persons at the booth that he was buying breakfast for migrant workers on his construction site and told them to use cardboard pulp as a pork substitute. Zi then filmed the process.

Zi also weaved in a conversation with one of the men, identified as Wei, in the video to make the story more convincing.

However, Beijing TV Station's statement didn't say why Wei did what Zi asked or if Wei was detained.

The video was broadcast on one of the channel's programs on July 8. It later was rebroadcast by China Central Television Station and carried by numerous Chinese media outlets. Shanghai Daily carried a story about the cardboard buns, based on the TV report.

Zi didn't appear on screen, but appeared to be an investigative TV reporter. He uncovered the dodgy buns in a shabby kitchen in the video.

The segment opened with a shot of cardboard piled in a heap between rows of shabby houses. A man, who was made to be believed as the booth owner, and a woman showed how they stuffed cardboard into buns to offset the rising cost of pork.

According to Zi's fake report, cardboard was soaked in water, and an industrial-use caustic soda, a poisonous chemical, was added. The cardboard lost its normal color, became softer and started to look more like pork. The concoction was then mixed with pork fat to make it more authentic.