are neighbours in same block responsible (also)for their guests actions ?

hi all,can anyon etell me neighbours in the same building are responsible for their friends/vistors actions towards other neighbours?
had a run in with some friends / visitors of a neighbour on the 5th floor this happened outside my door on the 2 nd floor.they were verbally abusive and behaved in the threatning manor towards me.
long story but to cut it short,they were noisy out my bathroom window 0130 hrs i tipped some water out the window they then shout 2 floor all came stamping upstairs like elephants then just before opening my flat door as i was going to apologise to my neighbour in a round about way when i heard some gurgling a flem and spitting sound,i opened the door and there was spit and flem all over it,my neighbour was up on her landing then her male friend started all the abuse and threating behaviour,he was dragged up by his gf then a female friend stated with me same things with her shout dont hit me!loud as too let every one hear it.something i would not do,am more a talk person rather than box but if need be to protect then i would .anyway i am going to visit the building president over this but would like to know where i stand.
thanks in advance