Just pasting a previous answer I've given to a similar question
Absolutely, and through the letters and speeches of Cicero we actually have a great insight into urban gang warfare in Late Republican Rome, specifically between the rival gang leaders of Milo and Clodius. Cicero had himself a deep rivalry with Publius Clodius, who was a rather shady but deeply ambitious gang-leader-for-hire who used his (adopted) public support and connections to back high ranking politicians such as Caesar and Pompey. The rivalry between Clodius and Cicero really peaked with Clodius having Cicero temporarily exiled from the city from 58-57. Even after returning there was a political battle between the two over the issue of Cicero's house, which had been torn down in his absence (and after returning, much to the anger of Clodius, Cicero successfully gained compensation and a right to rebuild it from the Senate). After only having returned a few months earlier and whilst rebuilding his house, we get an account from Cicero in the form of a letter to his best friend Atticus (Letter to Atticus 4.3) about an attack on him by Clodius and the subsequent gang warfare between Clodius and Milo (the opposing gang leader and therefore an ally to Cicero). A link to the whole letter will be provided below, but let me quote some choice sections that really reveal the extent of organized urban violence in the city:
"On 3 November an armed gang drove the workmen from my site, threw down Catalus' portico which was in the process of restoration by consular contract under a senatorial decree and had nearly reached the roof stage, smashed up my brother's house by throwing stones from my site, and then set it on fire. This was by Clodius' orders, with all Rome looking on as the firebrands were thrown”
As mentioned, Cicero's house had become a point of political contention between him and Clodius (see De Haruspicum Responso for more on this). Notice the open use of fire in a city that had a bad history with it.
“Accordingly, on 11 November as I was going down the Via Sacra, he came after me with his men. Uproar! Stones flying, cudgels and swords in evidence. And all like a bolt from the blue! I retired into Tettius Damio's forecourt, and my companions had no difficulty in keeping out the rowdies. Clodius himself could have been killed, but I am becoming a dietician, I'm sick of surgery.”
An armed ambush and presumably an attempted assassination attempt on Cicero by Clodius and his gang. Cicero’s ‘companions’ (whom must follow him around almost all the time given he wasn't expecting this) tough/armed enough to resist Clodius’ attack with ‘no difficulty’. Notice as well Cicero would feel killing Clodius would be 'surgery', he's just too tired to do it himself.
“On 12 November he tried to storm and burn Milo's house in the Cermalus, bringing out fellows with drawn swords and shields and others with lighted firebrands, all in full view at eleven o'clock in the morning. He himself had made P. Sulla's house his assault base. Then out came Q. Flaccus with some stout warriors from Milo's other house, the Anniana, and killed off the most notorious bandits of the whole Clodian gang. He had every wish to kill their principal, but he had gone to earth in the recesses of Sulla's house.”
Another attempt to attack and burn the house of a rival with armed men in the open day. Clodius himself is also using a house as an ‘assault base’. Then, Flaccus gets some ‘stout warriors from Milo’s other house’, implying that (at least in the case of Milo) there were armed men in or assembled at the houses of their bosses. Flaccus ‘killed off the most notorious bandits of the whole Clodian gang’ and ‘He had every wish to kill their principal’. Again, murderous retribution seems justified and accepted.
“On 19 November Milo went to the Campus before midnight with a large following. Though Clodius had a picked force of runaway slaves at his back, he did not dare go to the Campus. Milo stayed till noon, to the public's enormous glee and his own great reclame. The campaign of the three brethren became a fiasco. They found their violence outmatched and their fury treated with contempt.”
Milo imposes his gang on the Campus Martius, where elections and meetings could take place, effectively occupying it. There appears to be no legal sanction (as Metellus, an ally of Clodius, in attempting to stop this, rather than charging Milo, has to use some roundabout method of using Milo's auspice reporting duty to end the occupation instead, which doesn't even work) or even disapproval (instead the ‘public’s glee’) of this course of action. He was still doing so even when this letter was written on the 22nd.
“Clodius' party complain that it's all been my plan. Little do they know our heroic Milo, what a resourceful as well as gallant fellow he is. His spirit is amazing.”
“I think Publius [Clodius] will be brought to trial by Milo, unless he is killed first. If he now puts himself in Milo's way in a rough-and-tumble I don't doubt that Milo will dispatch him with his own hands. He has no qualms about doing so, and makes no bones about it.”
Cicero approves greatly of Milo's warfare with Clodius, and believes he would be entirely justified in killing him should they struggle again and he cannot bring him to court.
Notice we have an account of attacks on houses, arson, assaults, attempted assassination (in plain daylight on the Via Sacra, the main street of Rome, of all places), outright gang warfare, and even an armed occupation of the Campus Martius by Milo's gang. Notice as well this all happens in just the course of the month of November! And tellingly, even the usually non-violent Cicero speaks of Milo's actions with only approval. What we get is a picture where violence is prevalent, open, sometimes approved and frequent. And this isn't even a period of civil war or political unrest, just seems to be standard and expected by all parties involved.
In fact Cicero would not only go on to speak with great approval over Milo's warfare with Clodius again, but that last prediction of his would indeed turn out to be true. Whilst travelling outside of Rome, Milo and Clodius happened to have a chance occurrence whilst both travelling with attendants on the Via Appia which resulted in a brutal fight and Clodius' death (upon hearing of this Clodius' gang and supporters would even riot and burn down the Senate house). Milo was charged with his murder, and Cicero came to his defence with the famous Pro Milone, an interesting legal defence of which the main argument was that murdering Clodius was in fact no bad thing for Rome. I don't have the time right now to go into in depth, so I'll just state that the defence failed, but all the same demonstrates the length to which even Cicero was willing to not only accept but even endorse violence and gang warfare when it supported his political goals.
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