"We met Mumbai CP Rakesh Maria and brought to his notice the events leading to the unsavoury incident," Desai said.
Maria has assured a thorough probe, Desai said.
The situation was unprecedented and akin to a war between two countries, Desai felt.
Stones and soda water bottles were used to attack Shiv sainiks. Some women activists were injured in the caning by police later, he added.
"If the assailants were not MNS, was there somebody else who orchestrated the attack?" he asked.
Asked if Congress-NCP facilitated Thursday's incident, Desai said, "Maybe, as they realise that they don't have any chance of winning the poll."
Sena candidate from South Mumbai, Arvind Sawant said the police presence was more than necessary and he was kept waiting for half an hour at the Collectorate entrance.
Leader of Opposition in Council, Vinod Tawde said police should have made adequate arrangements to avert any such incident.