Residents of a town in Russia’s Murmansk region were recently witnesses to a bizarre incident in which a large part of a bridge went missing.

Aerial footage circulated on Russian social media showed that the two corner sections of the bridge over the Umba river, near the abandoned settlement of Oktyabrskaya, were intact, but the central part had mysteriously disappeared.

The Independent reported that speculation on VK, a Russian social media platform, was that thieves took down the bridge and scrapped it for metal. In pictures posted on the site initially, debris of the fallen bridge was seen in the water below but after a few days, there was no sign of the structure, which was about 75 feet long and weighed over 50 tonnes.

The identity of the alleged thieves and the method they used to steal the bridge was unknown. A criminal investigation was launched to look into the possibility of a theft.