RAWALPINDI, Dec 1: Panic gripped the city Saturday night when an explosive device detonated outside the house of a businessman in Shakrial (Sadiqabad).

The blast damaged the house and shattered window panes of adjoining houses. No one was injured.

The device had been planted outside Sher Wali Khan`s house.

Mr Khan hails from Mohmand Agency, but has been residing with his family in Sadiqabad since 2000.

`I was sleeping when the explosion outside my house woke me up at around 12:45am. I unlocked the gate which had been damaged by the explosion, and found window panes of adjoining houses shat-tered and shrapnel scattered in the street,` Sher Wali Khan told Dawn.

When asked whether he had received any threats from militant groups or extortionists, he said: `I have never received any letter or call from any terror group.

He added that he had no idea no enmity.

According to a bomb disposal expert, the device contained 10 ounce of `high intensity explosive water gel` which had been remotely detonated with a cellphone.

He said it was the second time a cellphone had been used to activate an explosive device in the city.

`A cellphone was used by a terrorist to detonate a bomb in AyubNational Park in 2006,` a bomb disposal expert told Dawn.

On the other hand, the police initially believed the explosion was caused by a firecracker but later maintained it was a bomb explosion.

CPO Akhtar Umer Lalika said the explosion was of low intensity, contradicting the bomb disposal squad`s view.

He said the police were investigating the issue to determine whether or not it was the outcome of old enmity.

`Apparently, it seems to be a prank of some sort,` CPO Lalika said. However, the police registered a case under the explosive act and anti-terrorism act against unidentified persons.