He suffered brain damage, lost the ability to speak and was paralyzed on his right side.
Although initial reports said Leja's chances of survival were extremely slim, he managed to live.
He was awarded the George Medal in January 1964 for conspicuous courage and outstanding devotion to duty.
Jean-Denis Lamoureux, a member of the FLQ who participated in the planting of the bombs, was subsequently jailed.
In 2013, a movement was launched to have the Quebec National Assembly declare Walter Leja a hero.