Colombo: A blast was heard on Thursday from vacant land behind the magistrates’ court in the town of Pugoda, 40km (25 miles) east of the capital Colombo, police and local residents said.
Police said they were investigating the explosion, which came at a time of high tension in Sri Lanka following the Easter Sunday suicide bomber attacks on the island state that killed 359 people and wounded about 500. Quoting a police spokesperson, Sri Lanka's news network News 1st said no damage had been reported.
Local media also reported that the road opposite Bandaranaike International Airport was re-opened after being temporarily closed due to a suspicious vehicle. Operations at the airport, which were suspended, also returned to normal. The Kurunegala bus stand was also evacuated and special search operation is underway.
Nine suicide bombers, believed to be members of a local extremist group called National Thowheed Jamath (NTJ), carried out a series of devastating blasts that tore through three churches and three luxury hotels on Easter.
Outrage over the terror attack rose after the Sri Lankan government admitted that "major" intelligence lapses led to the horrific blasts and asked two top security officials to resign. The Islamic State has claimed responsibility for the attacks and identified the seven suicide bombers who carried out the devastating blasts.
Giving information on the suicide bombers, the police said that the attacks at the Cinnamon Grand and Shangri La Hotels had been carried out by two brothers.
The Cinnamon Grand Hotel bomber had booked himself into the hotel on the previous night. CCTV footages have shown his breakfast table where he was seen consuming pieces of fruit and taking a walk around the restaurant before exploding himself.
Their younger brother has also been nabbed by the police. The house search had led to the discovery of extremist literature, a computer hard disk and SIM cards, thought to have been used to coordinate the blasts.
The police has already arrested the accomplices of the bomber of the lodging house near the National Zoo at the Colombo suburb of Dehiwela. The taxi driver who had taken him to the lodge was also arrested, the police said. The police suspected the bomber may have been targeting the nearby St Mary's Church where a large gathering was present at the Easter mass.
However, the presence of police at the church, who were there due to a previous break into the church by thieves, had prevented the bomber's entry into the church, officials said. The Education Ministry said the reopening of schools had been put off till April 29.
A state of emergency remains in effect to prevent further attacks. The emergency powers allow the security forces to crackdown in law and order breaches by sudden searches of property, arrests and detention of people indefinitely.