The deceased identified as Basant Madoria, 30, Raja Dakolia, 33, and Bhaskar Dalvi, 54, were stabbed around 10-15 times and their bodies were found lying in a pool of blood by a sweeper at around 8 am, police said.
While Madoria and Dakolia were working as waiters at Natraj Bar, Dalvi as the watchman, police said.
"The sweeper found the gate (of the bar) half open and found Dalvi's body lying there, after which he informed the owner of the bar Shaildndra Singh," said a police source.
Singh and the sweeper later found the bodies of two other victims Madoria and Dakolia in the garage situated on the premises of the bar.
According to the police, Madoria and Dakolia were working in the bar for the past five years while Dalvi for 12 years.
Police said Madoria and Dakolia, who would work late hours in the bar, would often sleep in the garage for few hours to take the first train to go to their destinations.
The bar was closed at 2:30 am by its staff after carrying out regular cleaning work of the premises and furniture. "CCTV cameras were also switched off before closing the bar as per the routine", police said.
Police suspect that the murders might have taken place somewhere between 2:30 am and 5 am.
While no weapon was found at the spot, the police said that prima facie robbery did not seem to be the motive as nothing has gone missing from the place.
"The killings could be the fallout of a personal rivalry," said the police.
"Dalvi and Madoria were killed when they were asleep, whereas Dakolia's body was found few meters away from the garage. Dakolia might have been chased and killed by the assailants as it seems he tried to escape," said a police official.
Around 20 persons, including female singers, are working in the bar and police are recording their statements.
Meanwhile, one of the employees told the police that he had last seen the victims before 4:30 am when he left the place. Police are verifying his claims.
Sniffer dogs picked up the trail to Vidhyavihar railway station, close to Tilak Nagar, before losing it.
Police said they have recovered a wristwatch from the bar, which they suspect to be that of one of the attackers.
Police have registered a case of murder against unknown persons and formed ten teams to crack the case.