Security forces have arrested three suspects allegedly involved in the attack on MP Mustafa Alloush.
Alloush, a member of Future Movement, and his bodyguard were pelted with stones and bottles on Friday in northern Lebanon during a protest demanding the release from jail of alleged Islamists.
Alloush had been invited by organizers of the protest in Tripoli to make a speech, but as he began to speak, demonstrators hurled bottles and stones at him.
He was hit by a stone and was slightly wounded.
Alloush said he believed the attack was "a spontaneous reaction."
"Preliminary investigation, however, showed that there was a group that wanted to target me physically," Alloush said in remarks published by the daily Al-Akhbar on Monday.
He said he did not press charges against anyone.