My son keeps hitting and throwing things

My son will be 16 months on the 16th. The past week or two he’s hit me in the face so many times! And it’s not like it’s an accident he’s doing it on purpose! And he’ll be playing with his cars and trucks because he’s obsessed with them at the minute and he’ll throw them at me, right in my face.

It’s not like I’ve told him off for anything it’s just completely out the blue! I tell him off for it and the he bursts out into tears!

How do I get him to stop doing this?