How did Tom kill his father?

[jekatiska]

No: HPFGUIDX 111501

I came accross an old thread about Tom Riddle's path to evil. It
struck me that we donn't actually know how he killed his father and
his grandparents. So far I have assumed that he used Avada Kedavra,
but as Moody said in GoF, it requires powerful dark magic. Tom was
only a teenager when he killed his father, and don't think he could
have used such a powerful curse at such a young age. Moreover,
undetected by the MoM, who would have tracked him down for the murder
of three people, I believe, even if he was 17 and allowed to perform
magic outside school. What if it was the Basilisk? Ok, the idea may
sound ludicrous, because when we met the Basilisk, it was very big
indeed. But what if it was a lot smaller 50 years earlier? Small
enough to be transported to Little Hangleton? What gave me this idea
was the fact that the three of them had frightened expressions on
their faces, like those petrified by the Basilisk, and unlike Cedric
who was killed by Avada Kedavra. Just a thought.

Jekatiska