Why have the most recent kidnappings in Mexico sparked such outrage?

It has been nearly six weeks since 43 students went missing in Iguala, Mexico, and the arrest of Iguala’s Mayor José Luis Abarca and his wife, Maria de los Angeles Pineda, is one of the first major steps that President Enrique Peña Nieto’s government has taken to get to the bottom of their disappearance. 

“We know this was the missing piece. If the federal authorities have completed the jigsaw puzzle, then this means we are closer to finding the students,” said the father of missing student Felipe de la Cruz.

The slow pace of the investigation may reflect the tangled web behind the kidnapping. Allegedly, a group of about 100 students from a teachers' college in Iguala had commandeered three buses — a practice not unusual for the students and largely tolerated by bus companies in the area — to travel to Mexico City for an upcoming march when policemen stopped the buses opened fire on the students, killing three of them and taking 43 others, it is suspected, on Abarca's orders.

"We want justice, because it's not fair our 43 colleagues have disappeared into thin air and three of our colleagues were killed, with others injured. This won't stop here. This does not solve anything. We want justice for our colleagues,” said student Juan Carlos Ocampo.

The investigation has authorities in an all-out search, and multiple mass grave sites have been discovered in the region, but none of bodies found so far have been identified as any of the missing students. Anger nationwide continues to flare. Tens of thousands of people are demonstrating in the capital, Mexico City, demanding answers.

The 43 students are part of an estimated 22,000 people who have gone missing in Mexico since 2006. Kidnapping is typically used by gangs to extort money and recruit new members, sometimes in collusion with local authorities. Many in the country have doubts whether authorities there are capable of resolving a problem linked so closely to those in power.

The arrest of Abarca and Pineda, who hoped to succeed him, is a sobering symptom of a class of public officials the people of Mexico can't trust and might well fear.

Why has this incident in Iguala — of all the disappearances — provoked a political crisis?

What is the deeper problem with Mexico's justice system, and what can be done?

Where does this leave Peña Nieto?

We consulted a panel of experts for the Inside Story.