Washington, Aug 3 (DPA) A Continental Airlines jet was forced to make an emergency landing in Miami Monday after encountering fierce turbulence that injured nearly 40 people.

Flight 128 was on its way from Rio de Janeiro to Houston Intercontinental Airport in Texas and was southeast of Puerto Rico at an altitude of about 10,973 metres when it encountered the turbulence, which was not part of a storm system, the Federal Aviation Administration said.

Approximately 28 passengers were treated for injuries at the scene, and another nine were taken to a local hospital, Bloomberg news reported. There were 168 passengers and 11 crew members on board the flight.

The plane landed in Miami at 5.35 a.m. (0935 GMT). There was no structural damage to the plane and no crew injuries, according to the FAA.

The Boeing 767-200 aircraft was approximately one hour from Miami when it encountered the turbulence, and the seat belt sign was illuminated, Continental said in a statement.

Turbulence accounted for approximately 22 per cent of air accidents between 1996 and 2005, and 49 percent of the accidents that caused serious injuries, according to the National Transportation Safety Board.