(Bloomberg) -- Sudanese security forces arrested 17 officers and are pursuing others for plotting an attempted coup, a member of the ruling military council said, in the latest upheaval to strike the North African nation since its long-time dictator was ousted.

The alleged coup bid came at a crucial time, just before the council was set to sign a power-sharing deal with Sudan’s main opposition group, Lt. Gen. Gamal Omar said in a statement on state-run Sudan TV. Those detained include 13 senior members of the army and national security services, he said.

Omar didn’t present any evidence, although witnesses described a heightened security presence in the capital, Khartoum, with troops positioned at key bridges, intersections and the main radio station.

Sudan, Africa’s third-largest country, has been roiled by sporadic coups, insurgencies and mass protests since independence in 1956. The military council has been in charge after nationwide demonstrations sparked by an economic crisis spurred it in April to oust President Omar al-Bashir -- an army officer who had himself seized power in 1989.

The country’s firebrand opposition movement has kept up its protests, despite a security crackdown that’s claimed more than 100 lives, accusing the council of trying to block a genuine transition to democracy. Under the yet-to-be-signed deal agreed last week, military and civilian representatives would share power on a sovereign council for just over three years before elections.

(Updates with heightened security in capital in third paragraph.)

To contact the reporter on this story: Mohammed Alamin in Khartoum at malamin1@bloomberg.net

To contact the editors responsible for this story: Alaa Shahine at asalha@bloomberg.net, Michael Gunn, Vishal Persaud

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