Four days after the deadly serial blasts, a fresh explosion was reported on Thursday in Pugoda on the outskirts of the Sri Lankan capital Colombo, police said, adding that there were no casualties or damages.

Police said the explosion was reported in a garbage dump behind the Pugoda Magistrate’s Court.

Spokesman Ruwan Gunasekera said the police was investigating the matter adding that it was not a controlled explosion like other blasts in recent days.

In the Easter Sunday bombings that targeted churches and hotels in Sri Lanka, at least 359 people were killed and over 500 others were injured.

So far 60 suspects have been arrested.

On Tuesday, the Islamic State or the ISIS had claimed responsibility for the deadly attacks without providing any major evidence.

The country’s deputy defence minister Ruwan Wijewardene had earlier told the parliament that an initial probe into deadly suicide bomb attacks in Sri Lanka revealed it was a “retaliation for Christchurch.”

The blasts targeted St Anthony’s Church in Colombo, St Sebastian’s Church in the western coastal town of Negombo and Zion Church in the eastern town of Batticaloa around 8.45 am (local time) as the Easter Sunday mass were in progress.

Explosions were also reported from three five-star hotels — the Shangri-La, the Cinnamon Grand and the Kingsbury in Colombo.

Meanwhile, India is learnt to have sent as many as three alerts before the deadly bombings in Sri Lanka, the last one being sent just hours before the carnage.

India had alerted Sri Lanka as early as April 4 to the possibility of imminent suicide attacks which became a reality on April 21.

The inputs were sent through diplomatic channels to the island nation after a thorough investigation pertaining to the ISIS case in Coimbatore was carried out by the NIA, which has filed a charge sheet against seven people.

During investigation, the probe team had stumbled upon videos of National Thowheed Jamaat (NTJ) leader Zahran Hashim, which was indicative of a terror attack on the Indian High Commission in Colombo.

After further investigation which included cyber trailing of some of the accounts associated with the ISIS, the central security agencies shared inputs with their Lankan counterparts about the churches being the likely target of the ISIS module.

(With agency inputs)