The inauguration of Mexico's new president was marked by demonstrations all around Mexico City Saturday, as well as clashes between police and protesters who continue to call Enrique Peña Nieto's new administration fraudulent.

According to RT, hundreds of demonstrators encountered authorities outside the national congress as Peña Nieto took the oath of office, with many of them throwing rocks, Molotov cocktails and firecrackers, and police firing tear gas and rubber bullets in response as protesters also moved to break up barricades surrounding the ceremony.

"They had to fence the damn place off," one masked protester told CNN. "[They are] faking democracy, faking institutional order."

Several instances of vandalism were also reported during the day, with protesters breaking storefront windows and, in Guadalajara, Jalisco, a demonstration by 300 students also allegedly included rocks being thrown at the local offices of the state-run network Televisa. Organizers of the protests denied being associated with such actions.

In another part of the capital city, Andres Manuel López Obrador, who finished second to Peña Nieto in the official election tally, held a rally of his own decrying the violence.

"That's the best thing for those in the mafia power circles: that there be confrontations, that there be violence," López Obrador said. "That way, they win."

Peña Nieto's ascendance to the nation's top office has been disputed since the very beginning: more than half of the ballots used in the country's presidential election on July 1 had to be recounted following allegations by thousands of Mexico City residents that they had been promised gift cards for voting for him.

The candidate of the Institutional Revolutionary Party (PRI) subsequently won the recount, which was also disputed by López Obrador.

But the outcry against Peña Nieto, buoyed by the Yo Soy 132 movement ("I am 132"), continued, with protests taking place at Independence Day celebrations across Mexico on Sept. 16. While Yo Soy 132 had relied heavily on social media to organize supporters leading up to Saturday's demonstrations, the group's Twitter account had been suspended by Saturday night.

Watch footage from Saturday's protests in Mexico City, posted on YouTube by TelenoticiasMX2012, below.