At least two people have been detained after a “Free Speech Rally” on the Common sparked heated confrontations with counter-protesters.

Two people could be seen being taken away in handcuffs about 1:45 p.m. after one of the free speech demonstrators crossed a police barrier in an attempt to hand one of the counter-protesters a Pepsi — a move that appeared to be an attempt to mock a recent commercial that depicted a protester handing a cop a soda.

The apparent attempt at a joke set off a scuffle between the man and one of the counter-protesters that eventually led to punches being thrown.

The man holding the Pepsi could be seen throwing at least one punch with the can of soda still in his hand.

The two groups have been demonstrating since late this morning and the protests have remained mostly peaceful, though both sides have been shouting insults at each other while a line of Hub cops works to maintain order.

Developing…