Riot police whack fans with truncheons as flares thrown before fierce derby clash between Lazio and Roma

DISTRESSING footage circulating this afternoon appears to show Roma fans being beaten with truncheons by riot police.

Jose Mourinho's side take on Lazio this afternoon in a crucial Rome derby.

#DerbyDellaCapitale Tensions entre #ultras de la #Roma et la Police, avant le match. Un policier blessé sur la Piazza Mancini. À l'obélisque, un groupe #CurvaNord #Lazio a tenté d'entrer en contact avec les #romanisti, après avoir quitté le Ponte Milvio. Intervention de la Police pic.twitter.com/ZI7HPIOCgy

Prior to the match, clips emerged on social media of confrontations between Roma supporters and police.

Some videos show fans being whacked by cops, while flares were also thrown,

One Ultras account tweeted a video while recounting their impression of what happened.

They wrote: "Tensions between #ultras of #Roma and the Police, before the match.

"An injured policeman in Piazza Mancini.

"At the obelisk, a group #CurvaNord #Lazio attempted to make contact with the #romanisti , after leaving the Ponte Milvio. Police action."

Italian football has already been hit with ugly confrontations between fans and police this week.

Napoli's Champions League clash with Eintracht Frankfurt saw cars set alight and cops reportedly attacked.

It was claimed that travelling Frankfurt fans were responsible for causing the chaos.

The scenes saw 800 cops deployed on the streets, with a reported 300 fans causing mayhem and resorting to violence.

This afternoon's Rome derby could have a huge say on determining where both teams finish in the Serie A table.

Maurizio Sarri's Lazio go into the match third - two points above their fifth-placed fierce rivals.