A huge haul of marijuana and seizure of over half a dozen mobile phone SIM cards in the past three months has brought Chas Divisional Jail in Bokaro district under the scanner.

IG (prison) Satyendra Singh shot a letter to jail superintendent Pravin Kumar on Tuesday, seeking an explanation on why security gaps had not been plugged in a facility that houses 300-odd inmates, 30 of them hardcore Maoists.

Stating that there were reports of outlaws — as many as 14 crime lords are lodged in Chas jail — running extortion rings from inside the prison, Singh also sought to know the reason behind the delay in installation of 3G jammers that can block signals from even high-end cellphones.

Speaking from Ranchi on Wednesday, IG Singh confirmed that he had sent a letter to the superintendent following reports that inmates, with help from Chas prison officials, were using cellphones to make extortion and ransom calls.

“I have directed strengthening of security and blocking use of mobile phones by criminals. Our objective is to make every jail in the state more secured,” the IG said.

Sources, however, pointed out that staff crunch needed to be addressed first. Of the 46 officials required to keep tabs on 309 inmates, Chas jail has only 26 on duty, including the superintendent and an assistant sub-jailer. The post of jailer and one of assistant sub-jailer remains vacant.

In 2007, half a dozen criminals had managed to escape from this porous jail, where a warden was also shot dead few years before that.