(BBC News) US airlines have cancelled dozens of flights into Mexico City over fears that ash from a rumbling volcano would affect their planes.

Delta and American were among the airlines cancelling more than 40 flights into the capital on Thursday.

Popocatepetl volcano has been rumbling all year, and began spewing ash and steam earlier in the week.

Airport authorities insisted there was no danger, and the US airlines said they had resumed flights on Friday.

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