Police believe a Mumbai crime boss hired the shooters for the June 11 hit on Jyotirmoy Dey but have yet to determine a motive for the killing, Mumbai joint police commissioner Himanshu Roy said.

“We will come back to you with a motive as we interrogate the suspects,” Roy said.

Gang leader Chhota Rajan is suspected of ordering the slaying and is believed to be hiding in Malaysia, Roy said.

Roy told reporters that the gang had followed Dey, the investigations editor of the Mid-day newspaper, on three motorcycles and in a four-by-four vehicle, before shooting him five times from behind.

The officer said the gang was paid 500,000 rupees ($11,000) for the contract killing and fled to a series of temple towns around the country in the immediate aftermath, where most of them were arrested.

The murder weapon, a US-made .32 revolver and 20 rounds of Czech-made ammunition, have been recovered, he added.

Mumbai Police commissioner Arup Patnaik added: “We do not know why he was killed. We don't have the answers at the moment.”

One of the men arrested is known to work for Rajan, who was once the right-hand man of Dawood Ibrahim, the Mumbai crime kingpin suspected of being behind the deadly 1993 Mumbai bomb blasts that killed more than 250 people.

Dey, who was 56, wrote extensively about gangland activities in Mumbai. His editor said at the time that the reporter was “a victim of his fearless journalism.”

His murder provoked outrage among Indian journalists, hundreds of whom took to the streets of Mumbai to demand greater protection from the state government and for a swift conclusion to the case.

All seven suspects are in police custody until July 4.