WASHINGTON – The government is fining Delta Air Lines Inc. $750,000 for bumping some passengers involuntarily, without offering compensation or seeking volunteers first.

Airlines sometimes sell too many tickets for a flight, and have to “bump” some fliers or move them to a later flight. If travelers don’t volunteer, the airline has to compensate them.

The Transportation Department said Wednesday it reviewed 310 complaints about how Delta handled overbookings between November 2010 and January 2012 and found numerous cases of noncompliance.