Update (1:30 pm ET): Flights at Heathrow have resumed, according to media reports.

* * *

Apparently, Heathrow couldn't install its new anti-drone system quickly enough.

According to reports in UK's ITV, the runway at London's Heathrow Airport - one of the biggest airport's in Europe - has been closed due to a drone sighting, in what sounds like a nightmarish re-run of the incident that recently shut down Gatwick airport for 36 hours during the middle of the holiday travel rush.

BREAKING

Heathrow airport's runway has been closed due to a possible drone sighting.

Here we go again...

— Steven Swinford (@Steven_Swinford) January 8, 2019

No departures at London Heathrow Airport amid reports of a drone sighting 😞 pic.twitter.com/vWYUNvgDLm

— Danny Lee (@JournoDannyAero) January 8, 2019

All departures have been halted while the Metropolitan Police investigate.

We are responding to a drone sighting at Heathrow and are working closely with the Met Police to prevent any threat to operational safety. As a precautionary measure, we have stopped departures while we investigate. We apologise to passengers for any inconvenience this may cause.

— Heathrow Airport (@HeathrowAirport) January 8, 2019

London

Cassandra Fairbanks, a US-based independent journalist, was departing from Heathrow after visiting with Julian Assange when her flight was grounded due to the drone activity.

My flight at Heathrow is grounded because of drones in the departure area

— Cassandra Fairbanks ✌️ (@CassandraRules) January 8, 2019

According to individuals who are waiting on their grounded flights, Heathrow's control tower has "no idea" when flights will resume.

Sitting on The runway at London’s #Heathrow Airport has been closed due to drone activity. The control tower has no idea when will be allowed to depart.

— Planet Ponzi (@PlanetPonzi) January 8, 2019

It's probably worth noting that the person or people behind the drone sightings that shut down Gatwick have not been caught.