Sidiki Kaba announced Saturday that two new prisons would be constructed, none has been built since the early 1960s.
A young father whose death in custody has spurred plans to build Senegal's first new prisons in five decades was killed by shots to the head, local media said Tuesday.
Ibrahima Fall, 33, was killed last week during a riot in the capital's Rebeuss prison.
His case has since become a focal point for prison reformers who have long despaired of the country's chronically overcrowded jails, with the government quickly promising to alleviate appalling conditions.
Fall's alleged crime -- buying a stolen sheep -- also shone a spotlight on Senegal's frequent use of pre-trial detention for even minor offences.
More than 700 of Rebeuss' 2,000-plus inmates tried to escape on September 20, leaving 27 prisoners and 14 prison guards injured after a violent confrontation with police.
Several Senegalese newspapers and RFM private radio cited Fall's autopsy as revealing "torso and head wounds," as well as "brain damage and copious bleeding caused by a firearm".
Fall left behind a wife and six-month-old daughter, causing an even greater outcry in the press and bringing condemnation from rights groups.
"The administration knew for at least six weeks that the situation was heading for a riot," said Amnesty International's Senegal director Seydi Gassama following Sall's death.
He called for an independent inquiry into the violence and said demands for greater scrutiny of long detention periods had been ignored.
Justice Minister Sidiki Kaba announced Saturday that two new prisons would be constructed, noting that none had been built since the early 1960s.
Rebeuss prison was built in 1929 to house 800 inmates, meaning it was at two-and-a-half times its maximum capacity when the riot broke out.
Images have long circulated of men detained in Rebeuss sleeping crammed together like sardines in a country where temperatures can reach 35 celsius (95 fahrenheit) in summer.