Smoke in the cabin has forced a US Airways flight from Spain to land in Boston, and an airline spokeswoman says four flight attendants went to hospital to be evaluated.
Spokeswoman Liz Landau said Flight 749 from Madrid was heading to Charlotte, North Carolina, with 192 passengers and a crew of nine, but had to land in Boston.
Ms Landau said the smoke had dissipated by the time the plane landed, and no passengers complained of any problems.
The plane has been taken out of service, and Ms Landau says mechanics are trying to determine what caused the smoke.
She said the passengers were put on another plane to Charlotte.