How, exactly, is it to be “nipped in the bud”, Geezer?
Provided they have broken no party rules the “infiltration” is nothing of the sort. It is merely people with a certain point of view joining and influencing an organisation for their own ends. They cannot be prevented from joining (a refusal would almost certainly be ruled unlawful by the courts) and once in, provided they abide by the party rules (which must also remain unmanipulated so as not to discriminate against them) they can propose policies and vote however they like. That is what democracy is all about and it is a process which will continue.
Those disliking such activities must join the organisation in large enough numbers so as to outnumber those with whom they do not agree. In places like Tower Hamlets (and indeed neighbouring Newham) this could prove very problematic. In TH in particular 33 of the 51 councillors are Muslims and the Muslim population accounts for about 42% of the electorate. Muslims control the local Labour Party and the local council. Lutfar Rahman, born in Bangladesh but brought up in TH, is the leader of the council
There are a number of places like this in the UK (although TH is currently the most extreme). No doubt they will become more numerous. It is too late to nip this in the bud. The die is cast. It is unreasonable to expect a population of mainly Bangladeshi Muslims to elect white middle class Conservative councillors and MPs. (In fact, TH never returned a Conservative Councillor in any ward until 2006, so it is nothing new).
Now if you are asking whether large numbers of a single nationality of immigrants should have been encouraged to congregate in one small area, or whether they should have been persuaded to disperse and integrate with the settled population, that is a different matter entirely.