raskoliti

1. (of wood, stone) to split; to cleave
   Raskolio je cepanicu jednim udarcem sekire. — He split the log with a single blow of the axe.
   Grom je raskolio staro drvo u dvorištu. — Lightning split the old tree in the yard.
2. (of a group, party) to split; to divide
   Spor oko kandidata raskolio je stranku. — The dispute over the candidate split the party.
   Posle izbora opozicija se raskolila na dve grupe. — After the election the opposition split into two groups.

With se it means 'to split up': stranka se raskolila.