How closely do you follow the rules at work? Some officials are outraged by the actions of a bus driver in Corsicana, Texas, who may have taken the phrase "by the book" a bit too far. Or in this case, not quite far enough.

It happened Thursday when a driver was ferrying released and paroled prisoners onboard a chartered Greyhound bus to a terminal in Dallas. As the clock struck 4pm, the woman behind the wheel checked her watch, pulled over to a convenience store about 100 kilometres from her destination and promptly told her 40 passengers that her shift was over and someone else would be coming to take them the rest of the way.

She then got off the giant vehicle and walked away. A stunned clerk inside the store saw what was happening and called police. They couldn't quite believe it, either. "In 31 years in law enforcement I've never seen anything like this," concurs Corsicana Police Sgt. Lamoin Lawhon.

Authorities called Greyhound and the prison and two officers were immediately dispatched to watch the former captives on board. When they arrived they found the prisoners, some wearing ankle monitoring bracelets, milling around the vehicle, trying to figure out what to do.

Four hours later, another bus finally rolled up to the small outpost in the middle of nowhere, carrying three bus drivers. To add insult to injury, the woman who originally left her post was among them.

Greyhound officials note their drivers do have strict guidelines about work and rest periods to ensure safety, and they're probing what happened in this case. A spokesman calls it a 'very serious matter.'

And as for the prisoners? Cops say they acted more responsibly than the driver who abandoned them. "Their behavior was exemplary," assess Officer Travis Wallace.