Swarms of the harmless insects have descended on Seoul and nearby cities, leaving many residents frustrated with the infestation.

SEOUL, South Korea -- Swarms of “lovebugs” are back in South Korea, blanketing a mountain peak, entering houses and sticking to car windows. Flying attached to one another while mating, the insects, known to scientists as Plecia nearctica, are also called united bugs, double-headed bugs or honeymoon flies.

SEOUL (Reuters) -Residents in and around the South Korean capital Seoul are complaining about swarms of black insects dubbed "lovebugs" covering hiking trails and ambushing people, as rising temperatures due to climate change spur their spread.