Complex sentence: One source of this information was Tronstad's old companion Jomar Brun, still in charge of the plant, who also helped people to flee the country by sea, via the Møre coast.
Split into simpler sentences: One source of this information was Tronstad's old companion Jomar Brun, still in charge of the plant. He also helped people to flee the country by sea, via the Møre coast.