The best line from the story:
"What motivated him to throw a puppy at the Hell's Angels is currently unclear," a police spokesman said.
Looking for a motive for a drive-by puppy throwing may be a fruitless search.
Puppy thrown at German biker gang
A German student “mooned” a group of Hell’s Angels and hurled a puppy at them before escaping on a stolen bulldozer, police have said.