Armie Hammer -- Confronts 'Reckless' Ferrari Driver ... Cops Called

Armie Hammer and his friends created a Vespa blockade in Venice Sunday ... corralling a Ferrari driver they say was racing down a crowded street ... and it got so heated cops were called.

It happened at around noon on a very congested, hoity toity street in Venice -- Abbot Kinney. Armie and his friends were cruising around on their Vespas when they say the Ferrari driver roared down the street, creating a hazard for cars and pedestrians.

Armie told cops he and his friends were alarmed and created a blockade with their bikes so the Ferrari driver would be trapped. Armie claims the driver then tried to wedge his way out of the blockade and almost struck his friends.

Things got heated and cops were called. Officers calmed everyone down and didn't ticket anyone.

You see people on the East Coast ... it's not all fun and games in 80 degree beach weather.