Four stray dogs have been causing major chaos at Haneda Airport since Wednesday after they were seen wandering around the runways, causing a delay in 18 flights altogether, before some of them were eventually captured.

The presumably stray dogs were first noticed on Wednesday, when an arriving plane was forced to abort its first landing and try again, Fuji TV reported. The four dogswere wandering around the runway and resting on the grass.

One of the four was captured on Wednesday, two at around 3:30 p.m. on Thursday and one is still on the loose, Haneda Airport officials confirmed. The three captured dogs were sent to an animal care center.

A total of 18 flights have been delayed as a result of the quartet's presence, with one arriving flight being redirected to Sendai Airport on Thursday.

Airport officials are currently trying to capture the last "trespasser," as well as investigate how they got onto the runway in the first place.