Who is responsible for AI?

More and more AI is present in our everyday lives, tech companies are using the huge amount of data available to them to make better predictions, track our behaviour and offer services they think we will use. As AI is being used in everything nowadays it begs the question of who is responsible for the decisions AI makes? What happens when AI systems fail and kill or harm someone? Can the AI system be held criminally liable for its actions? Criminal liability usually requires an action and a mental intent.