Four people were killed when a bus owned by Sky Express skidded off Interstate 95 in Virginia on May 31. After the crash, federal regulators suspended Sky Express’ license — though it’s apparently not stopping them from moving its buses around area roads.

According to WTOP, four Sky Express-owned buses were pulled over by Maryland State Police yesterday along the Beltway. The buses were spotted by a tipster; when cops pulled over the buses — who were not carrying any passengers — they found no logbooks, meaning it was impossible for them to determine whether they had been carrying any passengers recently.

The National Safety Transportation Board’s preliminary report on the crash found that the bus hit a guardrail, then flipped over and landed about 460 feet away from the road, but did not offer any specifics on what may have caused the accident. Kin Yiu Cheung, the driver of the bus that day who allegedly fell asleep behind the wheel, is facing several charges of vehicular manslaughter.

Sky Express’ website now simply states “Out of service.”