Santa Cruz de la SierraGunmen posing as couriers shot lawyer Nadia Beller.
The arrest tests whether Argentina’s former campaign strategist faces accountability.
Fernando Cerimedo has advised Milei, Bolsonaro and Bolivia’s president.
Prosecutors will ask a judge to order Cerimedo’s pretrial detention, Attorney General Roger Mariaca said.
Sources: The Telegraph, Al Jazeera Online, Bloomberg Business