After investigating further, police said Lanza assaulted an officer at the scene. He was charged with aggravated assault, resisting arrest and related offenses and was arraigned Tuesday morning.
Police said the brawl, which included as many as 100 people, started in the hotel bar among members of a wedding reception that was held at the Sheraton.
When a second wedding party - that of Nicole Sannuti and Michael Sofka - returned to the Sheraton after a reception elsewhere, they became embroiled in the melee, police said.
It's not clear which wedding Lanza was attending but he hails from the same New Jersey town as Matthew Sofka, 26, the brother of the groom in the Sannuti-Sofka wedding who was charged last week with aggravated assault and related offenses for allegedly fighting with a responding officer.
The identity of the second wedding party remains unknown.
Dino Privitera, an attorney representing the estate and family of Vincent Sannuti, the bride's uncle who died of a heart attack following the fight, said his firm is trying to confirm the identities of the wedding party that was already fighting when his clients returned to the hotel to help drop off gifts.
Sannuti, 57, a father of four, did not take part in the fight, nor did any member of his immediate family, Privitera said.
Sannuti was trying to move his family to safety outside one of the bar's exits when he collapsed into the arms of his son, Privitera said. He later was pronounced dead of a heart attack.
Privitera said he was retained by the family to handle media inquiries and stressed that litigation is not currently being considered.
However, a news release from his office highlights several concerns the family has about how the situation was handled, including whether Sannuti received "prompt and adequate medical care" and whether the hotel had "grossly overserved and grossly undersecured an unruly and drunken crowd of guests" from the other wedding party.
Privitera declined to go into detail about the allegations, except to say that there was "an inordinate amount of time" between when an ambulance was called for Sannuti and when one arrived. He also said that based on interviews with guests, there may have been a defibrillator at the hotel that was not working.
Contact Stephanie Farr at email@example.com or 215-854-4225. Follow her on Twitter @FarFarrAway. Read her blog at PhillyConfidential.com.