The government of India has notified the NTSB of an incident involving a AIRBUS A320 airplane that occurred on December 10, 2018. An Indigo Airbus A320 experienced an ECAM warning for 'Lavatory Smoke' while descending through FL170 to land Kolkata Airport (CCU), India. Flight crew declared an emergency and made a successful landing. Post landing inspection revealed that the No. 2 (right) engine was low about 13 quarts and a ground run of the engine found it to be the cause of the order odor and smoke. A borescope inspection of the engine found that the No. 3 bearing compartment seal was worn. The NTSB has appointed a U.S. Accredited Representative as the state of manufacturer of the engine to assist the government of India's investigation under the provisions of ICAO Annex 13. All investigative information will be released by the government of India.