Two persons including a man who allegedly opened fire outside Bollywood actor Salman Khan's residence in Mumbai have been arrested from Gujarat, police said on Tuesday.

The two persons - Vicky Gupta (24) and Sagar Pal (21) - both residents of Bihar, were nabbed late Monday night from Mata No Madh village in Gujarat's Kutch district, Deputy Inspector General of Kutch-West, Mahendra Bagadiya, said.

Based on technical surveillance, joint teams of the Kutch-West and Mumbai police nabbed the duo, he said.

They were handed over to the Mumbai police as the complaint is registered there, Bagadiya said.

A preliminary probe suggested that both Pal and Gupta were hired by the gang of incarcerated gangster Lawrence Bishnoi to open fire at Khan's house, he said.

While Pal did the firing, Gupta was in touch with the gang members, Bagadiya said.

At around 5 am on Sunday, two motorcycle-borne persons fired four rounds outside 58-year-old Khan's house at the Galaxy Apartment in Bandra area of Mumbai and fled the spot.

They had rented a house for a month in Navi Mumbai's Panvel, where the actor has a farmhouse, an official said on Monday.

The police on Monday questioned three persons from Navi Mumbai, including the house owner, the previous owner of the two-wheeler used in the crime, the agent who facilitated the sale, and several others as part of the probe into the firing incident, the official said.

The motorbike was abandoned near Mount Mary Church in Mumbai, a little over a kilometre from the actor's house, the police said.

A Facebook post claiming responsibility for the firing surfaced at around 11 am on Sunday.

The IP (Internet Protocol) address of the FB post was traced to Portugal and the police were verifying it, a senior official said on Monday.

Prima facie, the shooters had conducted a recce around the Galaxy Apartment in Bandra a few days ago, he said.

Police suspect a VPN (virtual private network) was used for uploading the Facebook post, allegedly by Anmol Bishnoi, the brother of jailed gangster Lawrence Bishnoi on Sunday, he said.

A VPN establishes a digital connection between a computer and a remote server owned by a VPN provider, creating a point-to-point tunnel that encrypts personal data, masks IP addresses, and allows the user to sidestep website blocks and firewalls on the Internet.