CAIRO — An Egyptian court today acquitted former leader Hosni Mubarak’s two sons and his last prime minister of corruption charges, a verdict announced just hours after security forces arrested a prominent activist as part of a crackdown against icons of the nation’s 2011 uprising.

The Cairo criminal court found Gamal and Alaa Mubarak and Ahmed Shafiq innocent of corruption in a case that arose from the 1995 sale of a plot of land to Mubarak’s sons by an association led at the time by the former prime minister, judicial officials said. Prosecutors claim the land was sold to the two at a price much lower than its market value.

Also acquitted were four retired generals who served as board members of the association.

Alaa, a wealthy businessman, and Gamal, his father’s one-time heir apparent, face a separate trial on other corruption charges.