By 112 Jugurtha resumed his war with Adherbal, penning the latter up in his capital of Cirta. Adherbal was encouraged to hold out by a corps of Italian residents, in expectation of military aid arriving from Rome. However, Roman troops were engaged in the Cimbrian War and the Senate merely sent two successive embassies to remonstrate with Jugurtha who delayed until he had captured Cirta. His troops then massacred many residents including the Italians. This brought Jugurtha into direct conflict with Rome, who sent troops under the Consul Lucius Calpurnius Bestia. Although the Romans made significant inroads into Numidia, their heavy infantry was unable to inflict any significant casualties on Jugurtha's army which included large numbers of light cavalry.
Bestia then accepted an offer of negotiations from Jugurtha, who surrendered and received a highly favourable peace treaty, which raised suspicions of bribery once more. The local Roman commander was summoned to Rome to face corruption charges brought by his political rival Gaius Memmius, who also induced the tribal assembly to vote safe conduct to Jugurtha to come to Rome to give evidence against the officials suspected of succumbing to bribery. However once Jugurtha had reached Rome another tribune used his veto to prevent evidence being given. Jugurtha also severely damaged his reputation and weakened his position by using his time in Rome to set gangs onto a cousin named Massiva who was a potential rival for the Numidian throne.
War again broke out between Numidia and the Roman Republic and several legions were dispatched to North Africa under the command of the Consul Quintus Caecilius Metellus. The war dragged out into a long and seemingly endless campaign as the Romans tried to inflict a decisive defeat on Jugurtha. Frustrated at the apparent lack of action, Metellus' lieutenant Marius returned to Rome to seek election as Consul. Successfully elected, Marius returned to Numidia and to take control of the war. He sent his Quaestor Lucius Cornelius Sulla to neighbouring Mauretania in order to eliminate their support for Jugurtha. With the help of Bocchus I of Mauretania, Sulla was able to capture Jugurtha and bring the war to a conclusive end. Jugurtha was brought to Rome in chains and placed in the Tullianum.
Jugurtha was executed by the Romans in 104 BC, after being paraded through the streets in Gaius Marius' Triumph.