COLORADO SPRINGS, Colo. —  A charter bus carrying at least 50 people rolled over on a slick highway in southern Colorado early Thursday, injuring some of the passengers.

The Colorado State Patrol said there were no fatalities when the crash happened on Interstate 25 around sunrise Thursday morning about 4 miles south of Walsenburg, which is about 90 miles south of Colorado Springs.

The bus, operated by Los Paisanos, was headed for its depot on Broadway in downtown Denver.

The patrol says the bus was traveling north when it rolled over into the median and landed upside down.

It was not immediately clear how many passengers were injured, but the patrol reported that none of the injuries appeared to be life-threatening.

A number of people from Denver were on the bus including Maria Rodriguez’s parents.

Rodriguez told FOX31, “I’m not sure exactly [my mother] has 4 or 5 ribs broken and my dad they says he’s ok but he says he feels a lot of pain on the left side… it’s hard for him to walk and hard for him to breathe…”

Rodriguez tells us her parents were returning from visiting family in Mexico.

Los Paisanos is based in Texas and has a “satisfactory” rating.

However, the FOX31 Problem Solvers discovered the company has been flagged for problems with the number of hours its drivers spend behind the wheel.

It’s drivers have been cited for “unsafe driving” including a high number of speeding tickets.

Colorado State Patrol says excessive speed for roadway conditions is considered a factor in this crash.

Back in Denver, the Rodriguez family tells FOX31 they’ve not been able to get any answers from the bus company.

“I came three times today… I came from Aurora and I think it’s very painful… They are not answering the phone,” said Rodriguez.

The accident remains under investigation.