Four Chinese sailors who were kidnapped last month in the port of Libreville, the capital of Gabon, have been released, the Chinese consulate in Lagos said.

A Nigerian security source separately told AFP Tuesday that the four had been freed in a military operation.

“The consulate general in Lagos cooperated with the relevant embassies and local Chinese enterprises and overseas Chinese groups to carry out rescue efforts, and the hostages were released safely,” according to a statement posted on the consulate’s website.