MOSCOW — Ending a nearly monthlong manhunt, security forces killed the husband of a suicide bomber who blew up a public bus last month in the city of Volgograd, Russian officials said Saturday.

Officials said the husband, Dmitri Sokolov, 21, was killed, along with four others identified as rebels, by security forces in Dagestan, a violence-plagued republic in the North Caucasus.

The bus bombing in Volgograd, which is about 900 kilometers (559 miles) south of Moscow, had unnerved the authorities because of its randomness and because instances of Muslim insurgent violence outside the Caucasus are relatively rare.

The bomber, Naida Asiyalova, blew herself up on a crowded No. 29 bus in the center of the city, killing six other passengers in a fiery blast that was recorded by the dashboard camera of a car traveling behind.