The incident took place in Outer Delhi late last night.
The gang was fleeing in a mini truck after stealing animals.
They opened fire at the police team which retaliated, police said today. Nobody was injured in the firing incident but four policemen were injured in stone pelting.
Police could not arrest the criminals, who abandoned the mini-truck in Narela, but managed to rescue some of the stolen animals.
"The operation to nab them started after a message was flashed on wireless that a group of Mewati criminals have been spotted travelling in Samaipur Badli area with stolen animals," a senior police official said.
Barricades were erected at several places and a mini truck was spotted at a police picket and was signalled to stop.
As they did not stop, police tried to chase the mini truck. The mini-truck driver hit the PCR vehicle while others started pelting stones at them.
The same truck was intercepted by another police van on Badli Road. But this time also, the criminals hit the police van and opened fire on policemen, who also retaliated. They then abandoned the vehicle and fled.
