Ford: ford taurus engine caught on fire, jumper cables, ford taurus

Question
my friend jump started his car with his fathers taurus. taursu hood shut..10 minutes later the taurus started smoking from the hood. friend opened the hood and the air i guess made flames come out.....car lost.

what did he do wrong not sure if he crossed the negative or positive jumper cables, or wheather the battery blew up causing the fire????.
do you have any idea why this happened...confused.  

Answer
It could be because the hood shut, the jumpers touched the body of the vehicle causing a spark.

Tell him to be carefull the next time he tries to jump start any vehicle. Always keep the two cables far apart from each other.

Chalmer John Desouza.