New Delhi: The NIA has raised to Rs 10 lakh the reward money for anyone providing information on the Delhi High Court blast even as the investigators suspect that clone of a SIM card was used to send one of the emails claiming responsibility for the last week's terror strike.

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Delhi serial blast 2008

The National Investigation Agency (NIA), which is probing the case, has raised the reward from Rs five lakh to Rs 10 lakh to encourage people to share information about the perpetrators of the blast with the investigators, official sources said.

Though the NIA has detained several persons suspecting their role in the blast or sending emails claiming responsibility for it, no one has been arrested formally so far as nothing incriminating has been found against anyone.

Sources said while tracking one of the four emails, the investigators have found that a clone of a mobile phone SIM card with Internet connection was used to send it, which proved to be difficult for the investigators to reach the actual sender of the mail.

"We have detained a person in West Bengal and he is being brought to Delhi for questioning but he may not be the actual sender of the email," a source said, indicating the complexity of the case.

Despite help from the sleuths of the ATS of several neighbouring states and the Delhi Police, the progress in the case is slow so far but investigators believe that some definite progress was expected in the next few days, sources said.

Delhi alert on 3rd anniversary of serial blasts

Delhi was put under tight security as it observed the anniversary of the serial blasts which claimed 26 lives here three years ago with security establishment taking no chance against the backdrop of the terror blast outside the Delhi High Court.

Over 20,000 armed personnel were deployed across the city who conducted a hawk-eyed vigil by carrying out searches in the wake of heightened threat perception.

The capital has been on high alert since September seven when a bomb exploded outside the High Court killing 13 persons and injuring over 70. The authorities had also received e-mails threatening to blow up shopping malls on Tuesday.

Checkings were carried out on vehicles, suspicious people and premises across the capital, a senior police official said.

The official said all precautionary measures were taken in view of the threat perception ahead of the third anniversary of September 13, 2008 blasts.

A series of five synchronised bomb blasts within a span of few minutes at various locations in the capital on this day had left 26 people dead.

Police have already strengthened security at shopping malls by deploying more personnel and conducting extensive searches.

The police official said the force is on high alert and they had intensified patrolling and checking across the city, including shopping malls, markets and other crowded places.

He said more people are being deployed and shopping mall operators have been asked to step up their security system. They are also being periodically briefed about the security arrangements they should make, he said. Police have also intensified checking at border points of the national capital.

Traffic police and civil defence personnel have alsop been roped in to check motorcyclists, DTC buses and keep a vigil on crowded places.
The traffic police will carry out checking of motorcycles and DTC buses while the civil defence personnel will be asked to remain alert at crowded places like shopping malls and markets. Their help would be taken for tenant verification.

Since Thursday, a day after the bomb blast outside the Delhi High Court, traffic personnel have been asked to conduct checking of motorcycles.

A traffic policeman posted near a bus stand will have to keep an eye on commuters and sometimes he will have to check the bus to ensure that no unattended baggage is lying behind, the official said.

According to Delhi Police statistics, a total of 7,308 motorcycles were checked since September 8, the day of the High Court blast.

"Till Dusshera, we have to be on high alert. We will be conducting extra searches. People may get inconvenienced. But we have to stay alert," the official said.