The absence of two key material witnesses – Low Taek Jho and Nik Faisal Ariff Kamil – will delay investigations into SRC International and 1MDB, sources say.

A source close to the investigations told Malaysiakini that Nik Faisal, the former director of SRC International, is a crucial witness to MACC’s probe into the company, while businessperson Jho Low is the main material witness in the 1MDB case...