Media outlets reported citing Army spokesman Colonel Issa Bangura on Monday that the 20 dead included 13 soldiers, three assailants, a police officer, a civilian, and someone working in private security.
He also added that eight people were wounded and three arrested.
Some 1,890 inmates escaped from the Pademba Road central prison after the attackers broke in, according to a situation report that prison officials shared with Reuters on Monday. So far, 23 have returned, it said.
In a two-hour raid, the assailants rammed open the main gate with a vehicle after gunfire and a rocket launcher failed to breach prison defenses, said Colonel Shek Sulaiman Massaquoi, the acting director general of the Sierra Leone Correctional Service.
The police urged inmates to return to prison in a statement on Monday and offered the public rewards for details on the whereabouts of escapees or the attackers.
AMK/PR