Austin, Texas (AP) A company that operates gas stations in several states -- including Colorado, has caught the attention of Texas officials, who claim the company is ripping off drivers at the pump.

Authorities say a weekend investigation found 990 pumps were rigged to favor Petroleum Wholesale by as much as one-tenth of a gallon for every five gallons sold. Pumps in violation were immediately shut down by Texas inspectors.

The company operates stations under the name Sunmart.

Texas Agriculture Commissioner Todd Staples says he suspects the pumps were intentionally tampered with to deliver less gasoline than they were supposed to.

He says it's not unusual for pumps to be slightly inaccurate, but the pattern of discrepancies at Sunmart stations was beyond the norm.

The investigation found that, across Texas, 990 of Sunmart's 1,704 fuel pumps were cheating consumers.

Petroleum Wholesale also operates gas stations in Oklahoma, Kansas, Utah and Arizona.

Authorities have not uncovered any violations in those states, but Staples says he has notified officials of his findings.