Story highlights Suspected twin suicide attacks happened minutes apart Saturday

24 people were injured in explosions in city of Maiduguri

(CNN) Female suicide bombers are suspected to be behind the twin explosions that rattled the northeastern Nigerian city of Maiduguri on Saturday near a refugee camp and a fuel depot, officials said.

The attacks targeted the city's Bakassi Internally Displaced Persons camp and the Nigerian National Petroleum Corp.'s Mega Filling Station, the Nigerian army said in a statement.

At least nine people were killed and 24 injured in the two explosions, according to the country's National Emergency Agency (NEMA).

In the first attack the suspected bomber ran into a crowd at the entrance of the Bakassi IDP camp, killing five people, the army said.

Ten minutes later and a mile away, a second blast killed three occupants on a motorized rickshaw at the entrance of a fuel depot owned by the National Oil Company. The army puts the total number of dead at 8.