The cause of the fire was not immediately clear, he said.

She said that the cause of the fire was under investigation.

Officials said the cause of the fire was under investigation.

The cause of the fire was still under investigation early today.

The cause of the fire was under investigation, the police said.

Officials said the cause of the fire was not yet known.

He said the cause of the fire is not known.

The cause of the fire was not known last night.

The cause of the fire was under investigation last night.

The cause of the fire is not known, and may never be, he said.