Prime Minister Salam Fayyad apologized Monday evening for the actions of Palestinian Authority security forces at a conference meant to protest the PLO's decision to return to direct peace talks.

"As prime minister, I am fully responsible for what happened and I apologize," Fayyad said during a news conference celebrating the "home stretch to freedom" and the start of the second year of the Plan of the 13th Government.

"As I feel sorry when I say that, I feel confident that it will never be repeated," he added calling "what happened on Wednesday ... obviously a big error."

Rights workers, media professionals and politicians said they were harassed -- and in some cases assaulted -- at what was planned as a moderate-sized conference voicing the opposition of several left-wing political parties, independent parties, and prominent business professionals to the resumption of peace talks.

According to news reports, dozens of PA security personnel and intelligence officers showed up at the conference at the Protestant Church in Ramallah and attempted to portray the event as a protest against the government.

Footage of the event was reportedly confiscated and several people said they were beaten by plainclothes security forces.

Police and security officials denied any involvement in the event, which they said was an "illegal riot" that was halted by police. President Mahmoud Abbas said earlier that he did not give the orders.