Patna, Jan 10 (IANS): A group of armed criminals looted cash and valuables worth 30 lakh from passengers on a train in Bihar's Lakhisarai district and assaulted some passengers, including women, who tried to resist, police said on Thursday.

The robbery took place on Wednesday night on the weekly New Delhi-Bhagalpur Express near Ghanauri halt in between Kiul and Jamalpur railway stations.

"More than two dozen armed criminals with their faces covered boarded the train earlier and stopped it by pulling the emergency chain at an isolated spot and then looted cash and valuables in five coaches," Government Railway Police official Sudhir Kumar Singh said in Jamalpur.

He said some passengers had lodged an FIR at Jamalpur railway station.

According to the passengers, the criminals also thrashed passengers who resisted them.

The train driver, P.N. Mishra, and his assistant Santosh Kumar told GRP and railway officials at Jamalpur that the robbery took place due to the absence of escort guard in the train in night, a railway official said.

A senior official, Shivender Anubhavi, said a probe will be conducted to know why there was no security escort in the train.