BRUSSELS • When Belgian police requested social media silence during a series of antiterrorism raids on Sunday, they might have expected a catty response from the Internet.

In fact, people politely complied but with a surreal twist, as thousands tweeted pictures of their feline friends when the hashtag #BrusselsLockdown went viral.

It began when Defence Minister Steven Vandeput tweeted: "Police are asking the public not to report their movements on social media, please support & rt #BrusselsLockdown."

Frustrated and anxious after the city spent a second day on its top state of alert, Belgian Twitter users responded bizarrely. Instead of taking pictures of what they could see or describing police operations, they posted pictures of cats.

"I think in one hour I've seen more #lolcats than I've seen in the rest of my life," said social media specialist Mateusz Kukulka, or @Mateusz.

He said he believed the first to have the idea was a cameraman for the Dutch television channel NOS, Mr Hugo Janssen or @Hoguhugo, who tweeted: "Instead of tweets about police activity in Brussels, here's a picture of our cat Mozart."

As the theme caught on, some posted photos of cats looking suspicious, or cats with guns and helmets, and even a surreal picture of two Star Wars stormtroopers riding hover scooters shaped like cats. As more users joined in, there was soon international support too: "Absolutely loving the #BrusselsLockdown hashtag! Amazing. Belgium is awesome," tweeted @SvenjaLiv from Ireland.

Afterwards, the Belgian authorities thanked social media users "for taking into account the needs of the ongoing operation". Belgian police yesterday also offered a virtual bowl of pet food to Internet cats as a gesture of appreciation.

"For the cats that helped us last night... help yourselves!" Belgian police said on their Twitter account, with a photo of a metal bowl with the police logo in French and Flemish, filled with cat food pellets.

AGENCE FRANCE-PRESSE