A US attorney is considering launching an investigation into oil giant Shell after thousands of its documents were found buried in the desert near Las Vegas.
Shell digs for an answer
The files buried 40 feet deep belonged to the Texas-New Mexico Pipeline Company, which is owned by Shell.
"I'm a bit curious why they was dumped in a hole 40 feet deep," district attorney for New Mexico Thomas Rutledge told the BBC.
"We are monitoring the situation to determine if there was a reasonable explanation as to why these particular records were buried or if there is potential criminal activity involved in disposing of these records."
The documents, which were buried near the company's pipeline, reportedly include environmental data, maps and financial ledgers.
Shell's spokesman in Houston, Tim O'Leary, told BBC News Online the company had launched an investigation.
"We don't believe this material is other than office refuse and stale data."
But he said Shell did not condone this type of dumping and the inquiry would continue.
The papers were found last Friday, 25 miles southeast of Las Vegas after a former employee of the Texas-New Mexico Pipeline Company told lawyers investigating an oil spill in the area of their existence.
"It's not in an area where you would normally throw things away," said Mr Rutledge.
"It's not next to a land fill where we would dispose of rubbish, especially that deep," he said.
Houston-based EOTT Energy, which recently bought some assets of the Texas-New Mexico Pipeline Company, is being sued by local residents because of environmental damage caused by a large oil spill from the pipeline.
The residents claim well water was contaminated by the spill in the early 1990s.
EOTT is counter-suing Shell, claiming that it was not responsible for the pipeline when the spill occurred and had not been informed of the environmental damage.