The present invention provides systems and methods for curing at least one leakage in a pipeline, the system including at least one fiber-in-sealant-in carrier fluid (FISIC) composition and at least one gel pig composition; wherein the at least one FISIC composition and the at least one gel pig form a pig train, are adapted to move along the pipeline to a region of the leakage and to seal and cure the at least one leakage.

The present invention provides methods and systems for sealing at least one leak in at least one of at least one lateral pipe and a mains pipe, the method including passing a at least one of a pig train and said sealant composition under pressure along at least one of said main pipeline and said at least one lateral pipe such that a portion of the sealant composition enters at least one leakage site to seal and cure the at least one leak.