There appear to be no survivors after a hot air balloon carrying at least 16 people caught fire and crashed in central Texas, authorities said.

The Caldwell County Sheriff's Office said in a statement on Saturday that investigators are determining the number of victims and their identities.

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Lynn Lunsford with the Federal Aviation Administration (FAA) said in an earlier statement that the accident happened shortly after 7.40am local time on Saturday near Lockhart, Texas, when the hot air balloon crashed into a pasture.

Lunsford said there were at least 16 people on board, adding that the FAA and the National Transportation Safety Board are going to the scene to investigate.

Lockhart is about 30 miles south of Austin.

National Transportation Safety Board spokesman Eric Weiss said that his agency's investigative team should arrive later on Saturday.

He said the safety agency knows "very, very little right now" about what happened.