Security measures at Alipore Central jail will be tighter with the installation of mobile phone jammers. A Telegraph picture

Devices to jam mobile networks will be installed at Alipore Central jail by March 31.

Judging by the success of the project, to be executed by Webel Electronic Communication Systems Ltd, the government will decide on installing the jammers at other ?supersensitive? jails in the city.

?This is an experimental project, being undertaken in the state for the first time,? said K.S. Rajendra Kumar, principal secretary in the department of jails.

?We are not sure how successful we will be. If everything goes right, we might think about installing the devices at Presidency and Dum Dum Central jails, too,? he added.

The devices will render mobile phones inoperative on the jail premises. There have been reports that some inmates are keeping contact with their accomplices outside through mobile phones brought in clandestinely. A section of the jail staff is allegedly involved in the racket of smuggling cellphones into the jail.

Inspector-general of Alipore Central jail B.D. Sharma, however, denied that there has been any report of ?misuse of mobile phone? at his jail.

But he admitted that ?easy availability and the size? make it convenient for the racketeers to smuggle cellphones into the jail.

The authorities have not yet decided on the number of jammers ? each will cost Rs 20 lakh ? to be installed. The target zones are the cells housing ?high-profile? criminals. The devices, however, will not disrupt the mobile network in residential estates or places adjacent to the jails.

J.N. Maity, director of Webel Electronic Communication Systems Ltd, said: ?Some parts of the device will be imported from Europe. The device will have a high directional antenna.?

The project was first handed over to Nalco. But due to a failure of its technology, the company could not instal the devices.