Rebel Shiv Sena MLA Sada Sarvankar allegedly fired a round during a clash between workers of the Uddhav Thackeray-led Sena and Maharashtra Chief Minister Eknath Shinde's camp early on Sunday, following which police registered a case against him, his son and some others, officials said.
Sarvankar, who represents Mahim Assembly constituency, however denied opening fire and claimed his rivals were trying to malign him.
He also said if police call him for questioning, he will cooperate with them.
Police also arrested five Sena workers from the Thackeray camp, who were later released on bail, they said.
The workers from both the sides first clashed in Prabhadevi area of central Mumbai shortly after Saturday midnight before indulging in a scuffle outside the Dadar police station some time later, where Sarvankar fired the round from a weapon, police said.
Both the groups lodged complaints against each other, following which the police registered first information reports (FIRs) against 10 to 20 members of both sides, they said.
The incident took place around 12.30 am in New Prabhadevi area, in which Sena functionary Santosh Talavane was allegedly attacked by Mahesh Sawant and 30 others, police said.
Talavane is part of the Shinde camp, while Sawant belongs to the Thackeray-led Sena.
The workers from both the camps again came face to face outside Dadar police station.
MLA Sarvankar, who was present there, fired one round, a police official confirmed.
After that, the legislator, his son Samadhan Sarvankar, Telavane and others were booked under sections of the Arms Act.
They were also charged for rioting and under other relevant sections of Indian Penal Code (IPC), he said.
As the rival groups lodged complaints against each other, the Dadar police registered two FIRs, including one against Sarvankar, an official said.
"There was a scuffle between two groups in Dadar in the early hours. Initially, one FIR was registered. Now, another FIR has also been registered under sections of rioting and the Arms Act," Deputy Commissioner of Police Pranay Ashok said.
Based on a complaint by Talavane, the Dadar police arrested five Sena workers, including Mahesh Sawant, another official said, adding that they were later released on bail.
The case against them was registered under various Indian Penal Code Sections including 323 (voluntarily causing hurt), 324 (voluntarily causing hurt by dangerous weapons or means), 504 (intentional insult with intent to provoke breach of peace) and 506 (criminal intimidation), he said.
Following their release, Sawant and other party workers went to 'Matoshree' to meet Uddhav Thackeray.
Party leader Aaditya Thackeray, who was present there, said Shiv Sainiks were the party's Brahmastra, a reference to the newly-released movie.
"In the Prabhadevi incident, Shiv Sainiks showed they were the party's Brahmastra and no one is bigger than them," he said.
The Shiv Sainiks sat next to Uddhav Thackeray, while Aaditya sat on the ground with some others.
"Shiv Sainiks are the real strength of the party and Shiv Sena is a family," he said.
Shinde camp's spokesman Naresh Mhaske later took a dig at Uddhav Thackeray saying that he found time from his afternoon nap to meet the persons released on bail following their arrest for attacking the member of the rival faction, and take a picture with them.
Earlier in the day, Shiv Sena MP Arvind Sawant, who supports former chief minister Thackeray, demanded action against Sarvankar under the Arms act for allegedly firing in public at the clash spot.
After meeting officials at Dadar police station following the arrest of workers of the Uddhav Thackeray faction, the parliamentarian said if those arrested are not released and action is not against Sarvankar, his party will take to streets and people will know which is the 'real Shiv Sena'.
He said after the Ganesh immersion, there was an argument and workers of the two Sena factions clashed around midnight.
Arvind Sawant alleged that Sarvankar verbally abused the rival group and fired twice in public.
The Sena spokesperson also claimed that police were a witness to it.
"When our workers went to Dadar police station to lodge a complaint, it was not accepted," he said.
Leader of Opposition in the state Legislative Council Ambadas Danve, who was present with Arvind Sawant at Dadar police station, told reporters that one-sided action by police cannot be tolerated.
"If both sides are at fault, action should be against both. We lodge a complaint, it is ignored. But when the other side complaints, our people are arrested at night," Danve said.
Kiran Pawaskar, spokesman of the Shinde group, rejected the allegations against Sarvankar.
"Sarvankar has Y category security and it is impossible that he will fire in public," Pawaskar said, adding that such allegations were 'childish'.
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