Most of the violence isn't actually by the shark.
David and another man enter the canals wearing wetsuits and scuba gear. A large shark preys on the two and in a sudden attack the Italian man is eaten. David is bitten in the shoulder but manages to escape to a cave.
When the shark does attack people there is a bit of blood.
People fire guns.
One man fights gun men there is blood and it is quite strong.
A man threatens to kill a man with a building tool.