A 56-year-old man allegedly killed and chopped his 32-year-old live-in partner into pieces using a tree cutter and then boiled them in a pressure cooker to dispose of them in Mumbai's Mira Road, police said. Manoj Sane killed Saraswati Vaidya some days back and was arrested on Wednesday. Around 12-13 pieces of Saraswati's body were found in their residence.