5 月 9 日（星期一）行車時間開始前，一列路軌打磨車正於將軍澳、坑口 至 康城 站間，作例行打磨路軌
當打磨車駛至康城站附近，近將軍澳車廠入口處時，其引擎突然起火，車上的職員隨即撲救，消防員亦奉召到場處理
至 0648 時，在消防處完成初步調查後，打磨車由其他機車拖走。而負責架空電纜、行車訊號、軌道、和基建設施的人員，因需時逐一檢查隧道內各種鐵路系統，故將軍澳 至 康城間只能維持單綫行車，至 0809 時為止
東隧過海列車因而比平日每小時少開四班車
涉事的路軌打磨車於 2015 年投入服務，原為南港島綫通車，從奧地利廠商「連勝家」（Linsinger）購置。而廠方人員將於日內到港，以調查起火原因，並跟進維修工作
A Rail Milling Train was carrying out routine rail polishing work between Tseung Kwan O, Hang Hau and LOHAS Park stations before the traffic hours of 9/May (Mon)
When the train was running between LOHAS Park Station and the entrance of Tseung Kwan O Depot, its engine suddenly caught fire. Staff on board put out the fire immediately and firemen were summoned to stand-by
At 0648 hours, the Rail Milling Train was hauled by other locomotives after Fire Services Department finished preliminary investigation. Various railway equipments including overhead lines, signalling, tracks and infrastructure inside the tunnel were checked thoroughly by MTR staff to ensure it was safe to reopen the line. During the course, single line traffic was maintained between Tseung Kwan O and LOHAS Park stations, until 0809 hours when normal operations were gradually resumed
Without LOHAS Park harbour crossing services, Eastern Harbour Crossing services were reduced by 4 trains per hour
The Rail Milling Train involved was originally purchased for South Island Line from the Austrian Linsinger and has served the #MTR since 2015. Professionals from the manufacturer will arrive Hong Kong in the next few days to investigate the root cause and follow up the maintenance work
