Vietnamese Internet users are experiencing slower service after thieves stole part of the one of the country's main fiber-optic transmission cables from the sea floor and sold it for scrap. If one more cable is cut, experts say, Vietnam could lose almost all of its telecommunications capacity. Matt Steinglass reports from Hanoi.

Traders monitor share prices at Securities Trading Center in Ho Chin Minh city, 20 December 2006

According to Vietnamese press reports, the country's military signed a contract last August with several companies to salvage undersea copper cable left over by the former government of South Vietnam, which fell to North Vietnamese communist forces in 1975.

The contractors, or someone else, apparently went on to "salvage" at lot more than that.

Lam Quoc Cuong, deputy director of the Vietnamese telecom company VTI, says a stretch measuring at least 11 kilometers of the operational fiber-optic cable serving present-day Vietnam is missing.

Cuong says the line was initially cut in March, and Vietnamese police are continuing to catch people selling illegally salvaged cable.

Last week, police in the southern coastal town of Vung Tau said they had captured four boats carrying a total of 100 tons of salvaged fiber-optic cable. The boats allegedly belonged to one man, a Vung Tau resident.

But VTI said the fiber-optic cable seized in Vung Tau does not match VTI's own cable, and must have come from some other line.

Police have not determined who initially cut the operational cable, or how they discovered its location. VTI's Cuong says finding the cable would have been difficult for the thieves.

He says the cable runs through different locations and at different depths. He says thieves might have found the cable by accident, while raising an anchor.

VTI says fixing the cable will cost $2.6 million, and take almost three months. Experts say if VTI's second undersea cable were cut, Vietnam could lose 82 percent of its telecommunications capacity.