Answer
Only a nuisance per se may be summarily abated without judicial proceedings; anything that is merely a nuisance per accidens must first be judicially declared a nuisance before it may be removed or destroyed. The Supreme Court has been strict on this point — it has struck down the summary demolition of things that were not nuisances per se, as in Cruz v. Pandacan Hiker's Club (G.R. No. 188213, 2016), where a barangay official who summarily destroyed a basketball ring without a hearing or an ordinance was held to have acted unlawfully.
Even where abatement is allowed, a private person who abates a public nuisance must follow the conditions of Article 704 — a prior demand upon the owner, refusal of that demand, approval by the district health officer, the assistance of the local police, and that the value of the destruction not exceed the amount fixed in that article — and the same procedure is indispensable for the extrajudicial abatement of a private nuisance (Article 706).