Incheon police on Tuesday said it is investigating what caused the mysterious explosion of an electric car last week, but some apartment residents in the greater Seoul area are already moving to ban electric vehicles from their underground parking lots.

An apartment complex in Anyang, Gyeonggi Province recently hung a banner saying EVs are banned from parking underground, in a measure decided via a resident meeting that took place after a parked Mercedes-Benz sedan spontaneously caught fire Thursday. Another complex in Eunpyeong-gu, Seoul, decided to move the EV-charging station from the basement levels to the ground-level, and not assign additional parking spots to electric cars for the time being.

The incident that spread fears about EVs happened in Incheon, west of Seoul, where a car parked for three straight days in the first basement level of an apartment complex caught fire. No casualties occurred outside of smoke inhalation for 20 residents, but the fire burned down 40 nearby vehicles and inflicted relatively minor damages on 100 more.

Officials at the Incheon Seobu Police Station said they plan to summon the Mercedes owner for questioning, in a bid to find what might have caused the fire. The car had been stationary at the spot for 59 hours without being connected to the charger, and surveillance footage showed no external factors that may have caused the fire.

As the exact cause of the fire is yet unknown, concerns over electric-car safety have escalated here. Local media reported Tuesday that a debate at one Gyeonggi-based apartment complex over banning EVs from underground parking lots led to a violent scuffle.

Another fire involving an electric vehicle occurred around 5 a.m. on Tuesday in Geumsan, South Chungcheong Province, when a sedan parked at a parking garage caught fire. This particular incident is thought to be a battery problem, based on the owner's testimony that he left a charger connected to the car at 7 p.m. the previous day, and that the preliminary investigation found that the fire started near the car’s battery.