BEIJING (Reuters) - Police in eastern China have detained 29 suspects linked to an abattoir that pumped up to 120 liters of water over a 12-hour period into cattle to inflate their slaughter weight before being carved up and sold, state media reported on Wednesday.

The reports did not specify what crime the suspects were being held for, but the case has provoked outrage on social media over the cruelty inflicted on the animals as images of their ghastly ordeal emerged.

From 7:00 pm till dawn, workers at the slaughterhouse would slowly pump water into cattle through tubes inserted into their nostrils before they were slaughtered for the market in nearby Nanjing, a provincial state-controlled TV broadcaster reported.

Stills from a video clip shot by an undercover reporter from the broadcaster showed a swollen cattle on its knees with tears in its eyes.

Workers whom the reporter spoke with said the process was cruel, though the foreman of the abattoir said the process was “painless”.

A number of social media users said the abattoir foreman should be pumped full of water instead.

“Cattle deserve to be treated with dignity too. Think about it, we should be grateful for their selflessness, which has helped fill our bellies,” one social media user wrote.

Beef from the slaughterhouse had been popular due to its prices, which averaged 30 yuan ($4.32) a kg, about 10 percent cheaper than its competitors, according to the broadcaster.

Consumption of beef in China is growing faster than for other meats. But with limited land to produce big herds to meet rising beef demand, China has been stepping up imports. Last year, China shipped in almost 700,000 tonnes of the red meat worth about $3.3 billion.

($1 = 6.9416 Chinese yuan renminbi)