RIO DE JANEIRO (AP) — As Associated Press photographer was punched and kicked Friday at a presidential campaign event in Brazil, though he did not suffer serious injuries.

The men who attacked photographer Andre Penner were in plain clothes and didn’t identify themselves, though they appeared to be working as crowd control. The incident occurred at a campaign event in Sao Paulo state for presidential candidate Aecio Neves and Sao Paulo Gov. Geraldo Alckmin.

Penner was amid a scrum of photographers caught between onlookers pushing forward toward the candidates and men trying to keep them back. One man punched him and three others joined in the attack.

In addition to assaulting Penner, they stole a camera and a lens from him. The gear was eventually returned by an unknown man who said he knew the assailants and persuaded them to return the items.

Neves’ spokesman, Otavio Cabral, said that he lamented the violence but that nobody from the Neves or Alckmin campaigns was involved.

Neves later called Penner, expressing regret about what happened and saying he repudiated the violence.

Police said they were investigating the assault.

Copyright 2014 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.