Chennai: Lakhs of BSNL mobile users were frustrated and fuming due to disrupted BSNL services for hours in Chennai, for the second consecutive day. The customers of state owned BSNL net work in the city, Coimbatore and the western regions of Chennai experienced service break down for hours.

Sources say the electrical snag at the Coimbatore switching unit had set off a crisis on the Haddows Road unit. The services were disrupted after the switching unit on Haddows Road crashed under the load of excessive call traffic.

Attributed to the unusually high congestion in the mobile switching centre on Haddows Road telecom hub, the problem resulted in making cellphones blank in the area served by the Coimbatore unit; mobile users seem to have made repeated attempts to land a particular number. Repeated dialing created virtual chaos.

According to BSNL officials, the problem was set right with a guidance from an engineer in the US. The Coimbatore switching unit has been fully restored. An estimated 2.50 lakh CellOne subscribers are parented to the Nortel switch on Haddows Road.

Officials say that calls got blanked only when a user entered the operational radius of the switch, which had undergone modification in the software only a couple of days ago. Troubleshooting at the Haddows Road unit was being guided by an engineer located in the U.S. who had logged on to the network, on Friday afternoon.

According to officials, the system was rebooted by 5 pm, and the network was expected to normal within a couple of hours.