Afterburner

Wondering if anyone has had this issue. I was working at the bench in my garage and noticed a flash come from the charger. Then a crackle and a wisp of smoke and another flash. I unplugged the charger and it flashed again with another wisp of smoke and that acrid electronics smell. Sure glad I was at the bench when it happened. Could have lost my garage. Anyone else have this issue? Charger was only a couple of years old and it was my spare, so rarely used.