(Adds background on Cofco)
By Hugh Bronstein
BUENOS AIRES, June 28 (Reuters) - Activity at ports operated by China's Cofco in Argentina's main grains hub of Rosario have been interrupted by a worldwide cyber attack, a local port manager said on Wednesday, the first sign that the virus has spread to South America.
The attack, first seen in Ukraine on Tuesday, has caused havoc around the world, crippling computers or disrupting operations at port operator A.P. Moller-Maersk, a Cadbury chocolate plant in Australia and the property arm of French bank BNP Paribas, among others.
"Cofco's system has been affected by the global attack. It has been infected by a virus. So they are working mechanically, not connected to their regular information system," Guillermo Wade, head of Argentina's CAPyM port operators' chamber, told Reuters in a telephone interview.
One of several ships scheduled to unload a cargo of fertilizer in Rosario had been halted since Tuesday, while a vessel loading wheat produced in the Pampas grains belt was interrupted for hours until local operators found a mechanical work-around to the attack, Wade said.
"It is affecting all of Cofco's port operations in Rosario," Wade added. "The cargo ship that was unloading fertilizer is still stopped. This has caused a backup in the line of other ships that have cargo to unload."
Cofco trades more than 78 million tonnes of grain a year worldwide, according to Chinese state media, and in 2014 agreed to buy Dutch grain trader Nidera and the agribusiness of Noble Group for more than $3 billion.
A local company representative did not immediately respond to a request for comment. Cofco is one of 43 export and port service companies that belong to the CAPyM chamber, Wade said. Cofco operates two ports in Rosario. Each has two berths used to load grains, oilseeds and byproducts, as well as unload fertilizers used by growers across the vast Pampas farm belt.
Argentina is the world's top exporter of soymeal livestock feed and the No. 3 supplier of raw soybeans, as well as a major global corn supplier. (Reporting by Hugh Bronstein; Editing by Bill Rigby)