A wedding video might hold vital clues as to who is responsible for an attack on guests at a reception at Lidcombe during the night.
Macquarie News understands police have siezed a tape from a wedding photographer at the Grand Westella reception centre which apparently shows the scene seconds after three men were stabbed outside.
The victims aged 18, 19, and 22 are in hospital this morning after surgery.
The trio were stabbed outside a wedding function centre after a fight between three guests, aged 18, 19, and 22, and several other men.
Violence erupted a short time later between 70 to 80 people who were concerned for the welfare of the injured men, police say.
Lidcombe resident David Bragg said there were about 20 police cars and a helicopter at the scene.
"There were dozens of cop cars swarming the area.
"Lines of cops were pushing people out of the Lidcombe CBD. It was quite a full-on thing."
A 19-year-old man has been charged with minor offences over the second incident, in Lidcombe, in which three men were stabbed.
The incident in Lidcombe was one of two multiple stabbings at weddings in Sydney's western suburbs overnight.
A 54-year-old man was arrested after another stabbing outside a wedding at a function centre on Station Street in Liverpool yesterday at 7.45pm (AEST), police say.
Police allege the male guest had become disruptive and was being escorted from the premises by three other guests, two men and one woman, when he produced a knife, slashing the two men, then the woman.
One man, a 28-year-old, sustained a severe laceration to his stomach, while the other, 29, sustained a deep laceration to his left forearm. The woman, 27, sustained a stab wound to her stomach.
All three remain in a stable condition in Liverpool Hospital.