At least 27 people -- mostly children -- were injured in a New York City school bus accident on Friday, according to Fox News.

Many of us rely upon school buses to transport our children safely. But poorly trained bus drivers, ill-maintained buses, and buses without seat belts or other safety devices pose a serious safety threat in the event of an accident. More than 140 people a year are killed in school bus accidents, according to the National Highway Traffic Safety Administration.

The New York TImes reports that the accident occurred on East 63rd Street between First and Second Avenue. There were apparently no other vehicles involved in the accident, although there are conflicting reports that the bus stopped short to avoid a collision and may have been rear-ended.

NY1 reported that the bus had just crossed the Queensborough Bridge and was waived into the intersection at 63rd Street and Second Avenue by a crossing guard. Another car cut off the bus, causing the bus driver to slam on the brakes.

The bus, from P.S. 149 in East New York Brooklyn, was en route to a class trip to Lincoln Center.

Several children were removed on stretchers and at least 11 victims were taken to area hospitals for treatment. The Times reported that 7 of the students were classified as "yellow tags" meaning the possibility of broken bones, while 17 others suffered minor injuries.