Nikon MH-18a quick charger: fast-blinking light?

When I charged the battery at the beginning it was blinking slowly/normally. Then after 1/2 hour it stopped charging and started blinking very fast and the battery/charger were very hot. (my batteries are genuine EN-EL3a)
Please give me idea. What should i do?

Fast blinking means the battery can't be charged because the battery got too hot or it is faulty.

Let everything cool down and try to charge it indoors in an air-conditioned environment away from sunlight or near a window. If the room temperature is above 95deg, it won't charge.

If you still can't get it to charge, then the battery is bad.

http://www.althephoto.com

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