Russian police had an unexpected encounter while searching a house in St. Petersburg — a crocodile in the basement.

In this undated handout photo released by the Russian Interior Ministry official website on Friday, Jan. 19, 2018, a crocodile rests in a small pool of water dug in a concrete basement in St. Petersburg, Russia.  (Russian Interior Ministry Press Service via AP)

In this undated handout photo released by the Russian Interior Ministry official website on Friday, Jan. 19, 2018, a crocodile rests in a small pool of water dug in a concrete basement in St. Petersburg, Russia.  (Russian Interior Ministry Press Service via AP)

The Fontanka.ru news portal said the incident happened Thursday while detectives were looking for undeclared weapons in the house of a man involved in staging reconstructions of historic military battles with period uniforms and antique weaponry.

When they went down, they saw a crocodile resting in a small pool of water dug in concrete basement. The owner of the house explained that he got the crocodile years ago.

In this undated handout photo released by the Russian Interior Ministry official website on Friday, Jan. 19, 2018, a crocodile rests in a small pool of water dug in a concrete basement in St. Petersburg, Russia. (Russian Interior Ministry Press Service via AP)

In this undated handout photo released by the Russian Interior Ministry official website on Friday, Jan. 19, 2018, a crocodile rests in a small pool of water dug in a concrete basement in St. Petersburg, Russia. (Russian Interior Ministry Press Service via AP)

City prosecutors said Friday they were checking whether the man was complying with local laws.