A Delta Air Lines flight from the Twin Cities to New York unexpectedly returned to its departure point soon after takeoff Thursday morning after an indicator went off in the cabin because of a "smoky odor," an airlines spokesman said.

The Boeing MD-88, Flight 1996 to LaGuardia Airport, left Minneapolis-St. Paul International Airport about 7:25 a.m. with 149 paying passengers aboard when a "lavatory detector was activated but no reports of anyone smoking," said Delta spokesman Morgan Durrant.

Durrant said the plane returned to an MSP gate "due to a smoky odor. … Technicians are taking a look."

The passengers were put on another aircraft and were expected to get into LaGuardia about two hours late, the spokesman said.

Twin Cities airport spokesman said these types of indicators are known to go off on planes when there is not an actual emergency.